diff options
| -rw-r--r-- | drivers/md/md.c | 1 | ||||
| -rw-r--r-- | drivers/md/raid1.c | 115 | ||||
| -rw-r--r-- | include/linux/raid/raid1.h | 3 |
3 files changed, 109 insertions, 10 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 64e7da3701a5..1364a1c97e6f 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -461,6 +461,7 @@ int sync_page_io(struct block_device *bdev, sector_t sector, int size, bio_put(bio); return ret; } +EXPORT_SYMBOL(sync_page_io); static int read_disk_sb(mdk_rdev_t * rdev, int size) { diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index c618015f07f6..b3856db8d6c2 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -191,6 +191,7 @@ static void reschedule_retry(r1bio_t *r1_bio) spin_lock_irqsave(&conf->device_lock, flags); list_add(&r1_bio->retry_list, &conf->retry_list); + conf->nr_queued ++; spin_unlock_irqrestore(&conf->device_lock, flags); wake_up(&conf->wait_barrier); @@ -245,9 +246,9 @@ static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int /* * this branch is our 'one mirror IO has finished' event handler: */ - if (!uptodate) - md_error(r1_bio->mddev, conf->mirrors[mirror].rdev); - else + update_head_pos(mirror, r1_bio); + + if (uptodate || conf->working_disks <= 1) { /* * Set R1BIO_Uptodate in our master bio, so that * we will return a good error code for to the higher @@ -259,14 +260,8 @@ static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int */ set_bit(R1BIO_Uptodate, &r1_bio->state); - update_head_pos(mirror, r1_bio); - - /* - * we have only one bio on the read side - */ - if (uptodate) raid_end_bio_io(r1_bio); - else { + } else { /* * oops, read error: */ @@ -653,6 +648,32 @@ static void allow_barrier(conf_t *conf) wake_up(&conf->wait_barrier); } +static void freeze_array(conf_t *conf) +{ + /* stop syncio and normal IO and wait for everything to + * go quite. + * We increment barrier and nr_waiting, and then + * wait until barrier+nr_pending match nr_queued+2 + */ + spin_lock_irq(&conf->resync_lock); + conf->barrier++; + conf->nr_waiting++; + wait_event_lock_irq(conf->wait_barrier, + conf->barrier+conf->nr_pending == conf->nr_queued+2, + conf->resync_lock, + raid1_unplug(conf->mddev->queue)); + spin_unlock_irq(&conf->resync_lock); +} +static void unfreeze_array(conf_t *conf) +{ + /* reverse the effect of the freeze */ + spin_lock_irq(&conf->resync_lock); + conf->barrier--; + conf->nr_waiting--; + wake_up(&conf->wait_barrier); + spin_unlock_irq(&conf->resync_lock); +} + /* duplicate the data pages for behind I/O */ static struct page **alloc_behind_pages(struct bio *bio) @@ -1196,6 +1217,7 @@ static void raid1d(mddev_t *mddev) break; r1_bio = list_entry(head->prev, r1bio_t, retry_list); list_del(head->prev); + conf->nr_queued--; spin_unlock_irqrestore(&conf->device_lock, flags); mddev = r1_bio->mddev; @@ -1235,6 +1257,74 @@ static void raid1d(mddev_t *mddev) } } else { int disk; + + /* 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 + * other devices. When we find one, we re-write + * and check it that fixes the read error. + * This is all done synchronously while the array is + * frozen + */ + sector_t sect = r1_bio->sector; + int sectors = r1_bio->sectors; + freeze_array(conf); + while(sectors) { + int s = sectors; + int d = r1_bio->read_disk; + int success = 0; + + if (s > (PAGE_SIZE>>9)) + s = PAGE_SIZE >> 9; + + do { + rdev = conf->mirrors[d].rdev; + if (rdev && + test_bit(In_sync, &rdev->flags) && + sync_page_io(rdev->bdev, + sect + rdev->data_offset, + s<<9, + conf->tmppage, READ)) + success = 1; + else { + d++; + if (d == conf->raid_disks) + d = 0; + } + } while (!success && d != r1_bio->read_disk); + + if (success) { + /* write it back and re-read */ + while (d != r1_bio->read_disk) { + if (d==0) + d = conf->raid_disks; + d--; + rdev = conf->mirrors[d].rdev; + if (rdev && + test_bit(In_sync, &rdev->flags)) { + if (sync_page_io(rdev->bdev, + sect + rdev->data_offset, + s<<9, conf->tmppage, WRITE) == 0 || + sync_page_io(rdev->bdev, + sect + rdev->data_offset, + s<<9, conf->tmppage, READ) == 0) { + /* Well, this device is dead */ + md_error(mddev, rdev); + } + } + } + } else { + /* Cannot read from anywhere -- bye bye array */ + md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); + break; + } + sectors -= s; + sect += s; + } + + + unfreeze_array(conf); + bio = r1_bio->bios[r1_bio->read_disk]; if ((disk=read_balance(conf, r1_bio)) == -1) { printk(KERN_ALERT "raid1: %s: unrecoverable I/O" @@ -1529,6 +1619,10 @@ static int run(mddev_t *mddev) memset(conf->mirrors, 0, sizeof(struct mirror_info)*mddev->raid_disks); + conf->tmppage = alloc_page(GFP_KERNEL); + if (!conf->tmppage) + goto out_no_mem; + conf->poolinfo = kmalloc(sizeof(*conf->poolinfo), GFP_KERNEL); if (!conf->poolinfo) goto out_no_mem; @@ -1635,6 +1729,7 @@ out_free_conf: if (conf->r1bio_pool) mempool_destroy(conf->r1bio_pool); kfree(conf->mirrors); + __free_page(conf->tmppage); kfree(conf->poolinfo); kfree(conf); mddev->private = NULL; diff --git a/include/linux/raid/raid1.h b/include/linux/raid/raid1.h index c55674252533..cbe4238d3f9f 100644 --- a/include/linux/raid/raid1.h +++ b/include/linux/raid/raid1.h @@ -46,6 +46,7 @@ struct r1_private_data_s { spinlock_t resync_lock; int nr_pending; int nr_waiting; + int nr_queued; int barrier; sector_t next_resync; int fullsync; /* set to 1 if a full sync is needed, @@ -57,6 +58,8 @@ struct r1_private_data_s { struct pool_info *poolinfo; + struct page *tmppage; + mempool_t *r1bio_pool; mempool_t *r1buf_pool; }; |