* raid_disks
* near_copies (stored in low byte of layout)
* far_copies (stored in second byte of layout)
+ * far_offset (stored in bit 16 of layout )
*
* The data to be stored is divided into chunks using chunksize.
* Each device is divided into far_copies sections.
* near_copies copies of each chunk is stored (each on a different drive).
* The starting device for each section is offset near_copies from the starting
* device of the previous section.
- * Thus there are (near_copies*far_copies) of each chunk, and each is on a different
+ * Thus they are (near_copies*far_copies) of each chunk, and each is on a different
* drive.
* near_copies and far_copies must be at least one, and their product is at most
* raid_disks.
+ *
+ * If far_offset is true, then the far_copies are handled a bit differently.
+ * The copies are still in different stripes, but instead of be very far apart
+ * on disk, there are adjacent stripes.
*/
/*
* With this layout, and block is never stored twice on the one device.
*
* raid10_find_phys finds the sector offset of a given virtual sector
- * on each device that it is on. If a block isn't on a device,
- * that entry in the array is set to MaxSector.
+ * on each device that it is on.
*
* raid10_find_virt does the reverse mapping, from a device and a
* sector offset to a virtual address
chunk *= conf->near_copies;
stripe = chunk;
dev = sector_div(stripe, conf->raid_disks);
+ if (conf->far_offset)
+ stripe *= conf->far_copies;
sector += stripe << conf->chunk_shift;
{
sector_t offset, chunk, vchunk;
- while (sector > conf->stride) {
- sector -= conf->stride;
- if (dev < conf->near_copies)
- dev += conf->raid_disks - conf->near_copies;
- else
- dev -= conf->near_copies;
- }
-
offset = sector & conf->chunk_mask;
- chunk = sector >> conf->chunk_shift;
+ if (conf->far_offset) {
+ int fc;
+ chunk = sector >> conf->chunk_shift;
+ fc = sector_div(chunk, conf->far_copies);
+ dev -= fc * conf->near_copies;
+ if (dev < 0)
+ dev += conf->raid_disks;
+ } else {
+ while (sector >= conf->stride) {
+ sector -= conf->stride;
+ if (dev < conf->near_copies)
+ dev += conf->raid_disks - conf->near_copies;
+ else
+ dev -= conf->near_copies;
+ }
+ chunk = sector >> conf->chunk_shift;
+ }
vchunk = chunk * conf->raid_disks + dev;
sector_div(vchunk, conf->near_copies);
return (vchunk << conf->chunk_shift) + offset;
return ret;
}
+static int raid10_congested(void *data, int bits)
+{
+ mddev_t *mddev = data;
+ conf_t *conf = mddev_to_conf(mddev);
+ int i, ret = 0;
+
+ rcu_read_lock();
+ for (i = 0; i < mddev->raid_disks && ret == 0; i++) {
+ mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)) {
+ request_queue_t *q = bdev_get_queue(rdev->bdev);
+
+ ret |= bdi_congested(&q->backing_dev_info, bits);
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+
/* Barriers....
* Sometimes we need to suspend IO while we do something else,
* either some resync/recovery, or reconfigure the array.
int i;
int chunk_sects = conf->chunk_mask + 1;
const int rw = bio_data_dir(bio);
+ const int do_sync = bio_sync(bio);
struct bio_list bl;
unsigned long flags;
mirror->rdev->data_offset;
read_bio->bi_bdev = mirror->rdev->bdev;
read_bio->bi_end_io = raid10_end_read_request;
- read_bio->bi_rw = READ;
+ read_bio->bi_rw = READ | do_sync;
read_bio->bi_private = r10_bio;
generic_make_request(read_bio);
conf->mirrors[d].rdev->data_offset;
mbio->bi_bdev = conf->mirrors[d].rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
- mbio->bi_rw = WRITE;
+ mbio->bi_rw = WRITE | do_sync;
mbio->bi_private = r10_bio;
atomic_inc(&r10_bio->remaining);
blk_plug_device(mddev->queue);
spin_unlock_irqrestore(&conf->device_lock, flags);
+ if (do_sync)
+ md_wakeup_thread(mddev->thread);
+
return 0;
}
seq_printf(seq, " %dK chunks", mddev->chunk_size/1024);
if (conf->near_copies > 1)
seq_printf(seq, " %d near-copies", conf->near_copies);
- if (conf->far_copies > 1)
- seq_printf(seq, " %d far-copies", conf->far_copies);
-
+ if (conf->far_copies > 1) {
+ if (conf->far_offset)
+ seq_printf(seq, " %d offset-copies", conf->far_copies);
+ else
+ seq_printf(seq, " %d far-copies", conf->far_copies);
+ }
seq_printf(seq, " [%d/%d] [", conf->raid_disks,
- conf->working_disks);
+ conf->raid_disks - mddev->degraded);
for (i = 0; i < conf->raid_disks; i++)
seq_printf(seq, "%s",
conf->mirrors[i].rdev &&
* else mark the drive as failed
*/
if (test_bit(In_sync, &rdev->flags)
- && conf->working_disks == 1)
+ && conf->raid_disks-mddev->degraded == 1)
/*
* Don't fail the drive, just return an IO error.
* The test should really be more sophisticated than
* really dead" tests...
*/
return;
- if (test_bit(In_sync, &rdev->flags)) {
+ if (test_and_clear_bit(In_sync, &rdev->flags)) {
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
mddev->degraded++;
- conf->working_disks--;
+ spin_unlock_irqrestore(&conf->device_lock, flags);
/*
* if recovery is running, make sure it aborts.
*/
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
}
- clear_bit(In_sync, &rdev->flags);
set_bit(Faulty, &rdev->flags);
- mddev->sb_dirty = 1;
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
printk(KERN_ALERT "raid10: Disk failure on %s, disabling device. \n"
" Operation continuing on %d devices\n",
- bdevname(rdev->bdev,b), conf->working_disks);
+ bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded);
}
static void print_conf(conf_t *conf)
printk("(!conf)\n");
return;
}
- printk(" --- wd:%d rd:%d\n", conf->working_disks,
+ printk(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
conf->raid_disks);
for (i = 0; i < conf->raid_disks; i++) {
tmp = conf->mirrors + i;
if (tmp->rdev
&& !test_bit(Faulty, &tmp->rdev->flags)
- && !test_bit(In_sync, &tmp->rdev->flags)) {
- conf->working_disks++;
+ && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
mddev->degraded--;
- set_bit(In_sync, &tmp->rdev->flags);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
}
}
for (i=0; i<conf->copies; i++)
if (r10_bio->devs[i].bio == bio)
break;
- if (i == conf->copies)
- BUG();
+ BUG_ON(i == conf->copies);
update_head_pos(i, r10_bio);
d = r10_bio->devs[i].devnum;
*
* 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;
* 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;
-
- do {
- int d = r10_bio->devs[sl].devnum;
- rdev = conf->mirrors[d].rdev;
- if (rdev &&
- test_bit(In_sync, &rdev->flags) &&
- sync_page_io(rdev->bdev,
- r10_bio->devs[sl].addr +
- sect + rdev->data_offset,
- s<<9,
- conf->tmppage, READ))
- success = 1;
- else {
- sl++;
- if (sl == conf->copies)
- sl = 0;
- }
- } while (!success && sl != r10_bio->read_slot);
-
- if (success) {
- int start = sl;
- /* write it back and re-read */
- while (sl != r10_bio->read_slot) {
- int d;
- if (sl==0)
- sl = conf->copies;
- sl--;
- d = r10_bio->devs[sl].devnum;
- rdev = conf->mirrors[d].rdev;
- if (rdev &&
- test_bit(In_sync, &rdev->flags)) {
- 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);
- }
- }
- sl = start;
- while (sl != r10_bio->read_slot) {
- int d;
- if (sl==0)
- sl = conf->copies;
- sl--;
- d = r10_bio->devs[sl].devnum;
- rdev = conf->mirrors[d].rdev;
- if (rdev &&
- test_bit(In_sync, &rdev->flags)) {
- 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 {
- /* 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;
(unsigned long long)r10_bio->sector);
raid_end_bio_io(r10_bio);
} else {
+ const int do_sync = bio_sync(r10_bio->master_bio);
rdev = conf->mirrors[mirror].rdev;
if (printk_ratelimit())
printk(KERN_ERR "raid10: %s: redirecting sector %llu to"
bio->bi_sector = r10_bio->devs[r10_bio->read_slot].addr
+ rdev->data_offset;
bio->bi_bdev = rdev->bdev;
- bio->bi_rw = READ;
+ bio->bi_rw = READ | do_sync;
bio->bi_private = r10_bio;
bio->bi_end_io = raid10_end_read_request;
unplug = 1;
int buffs;
buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
- if (conf->r10buf_pool)
- BUG();
+ BUG_ON(conf->r10buf_pool);
conf->r10buf_pool = mempool_create(buffs, r10buf_pool_alloc, r10buf_pool_free, conf);
if (!conf->r10buf_pool)
return -ENOMEM;
biolist = bio;
bio->bi_private = r10_bio;
bio->bi_end_io = end_sync_read;
- bio->bi_rw = 0;
+ bio->bi_rw = READ;
bio->bi_sector = r10_bio->devs[j].addr +
conf->mirrors[d].rdev->data_offset;
bio->bi_bdev = conf->mirrors[d].rdev->bdev;
for (k=0; k<conf->copies; k++)
if (r10_bio->devs[k].devnum == i)
break;
+ BUG_ON(k == conf->copies);
bio = r10_bio->devs[1].bio;
bio->bi_next = biolist;
biolist = bio;
bio->bi_private = r10_bio;
bio->bi_end_io = end_sync_write;
- bio->bi_rw = 1;
+ bio->bi_rw = WRITE;
bio->bi_sector = r10_bio->devs[k].addr +
conf->mirrors[i].rdev->data_offset;
bio->bi_bdev = conf->mirrors[i].rdev->bdev;
biolist = bio;
bio->bi_private = r10_bio;
bio->bi_end_io = end_sync_read;
- bio->bi_rw = 0;
+ bio->bi_rw = READ;
bio->bi_sector = r10_bio->devs[i].addr +
conf->mirrors[d].rdev->data_offset;
bio->bi_bdev = conf->mirrors[d].rdev->bdev;
mirror_info_t *disk;
mdk_rdev_t *rdev;
struct list_head *tmp;
- int nc, fc;
+ int nc, fc, fo;
sector_t stride, size;
if (mddev->chunk_size == 0) {
nc = mddev->layout & 255;
fc = (mddev->layout >> 8) & 255;
+ fo = mddev->layout & (1<<16);
if ((nc*fc) <2 || (nc*fc) > mddev->raid_disks ||
- (mddev->layout >> 16)) {
+ (mddev->layout >> 17)) {
printk(KERN_ERR "raid10: %s: unsupported raid10 layout: 0x%8x\n",
mdname(mddev), mddev->layout);
goto out;
if (!conf->tmppage)
goto out_free_conf;
+ conf->mddev = mddev;
+ conf->raid_disks = mddev->raid_disks;
conf->near_copies = nc;
conf->far_copies = fc;
conf->copies = nc*fc;
+ conf->far_offset = fo;
conf->chunk_mask = (sector_t)(mddev->chunk_size>>9)-1;
conf->chunk_shift = ffz(~mddev->chunk_size) - 9;
- stride = mddev->size >> (conf->chunk_shift-1);
- sector_div(stride, fc);
+ size = mddev->size >> (conf->chunk_shift-1);
+ sector_div(size, fc);
+ size = size * conf->raid_disks;
+ sector_div(size, nc);
+ /* 'size' is now the number of chunks in the array */
+ /* calculate "used chunks per device" in 'stride' */
+ stride = size * conf->copies;
+ sector_div(stride, conf->raid_disks);
+ mddev->size = stride << (conf->chunk_shift-1);
+
+ if (fo)
+ stride = 1;
+ else
+ sector_div(stride, fc);
conf->stride = stride << conf->chunk_shift;
conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc,
mddev->queue->max_sectors = (PAGE_SIZE>>9);
disk->head_position = 0;
- if (!test_bit(Faulty, &rdev->flags) && test_bit(In_sync, &rdev->flags))
- conf->working_disks++;
}
- conf->raid_disks = mddev->raid_disks;
- conf->mddev = mddev;
spin_lock_init(&conf->device_lock);
INIT_LIST_HEAD(&conf->retry_list);
disk = conf->mirrors + i;
- if (!disk->rdev) {
+ if (!disk->rdev ||
+ !test_bit(In_sync, &disk->rdev->flags)) {
disk->head_position = 0;
mddev->degraded++;
}
/*
* Ok, everything is just fine now
*/
- size = conf->stride * conf->raid_disks;
- sector_div(size, conf->near_copies);
- mddev->array_size = size/2;
- mddev->resync_max_sectors = size;
+ mddev->array_size = size << (conf->chunk_shift-1);
+ mddev->resync_max_sectors = size << conf->chunk_shift;
mddev->queue->unplug_fn = raid10_unplug;
mddev->queue->issue_flush_fn = raid10_issue_flush;
+ mddev->queue->backing_dev_info.congested_fn = raid10_congested;
+ mddev->queue->backing_dev_info.congested_data = mddev;
/* Calculate max read-ahead size.
* We need to readahead at least twice a whole stripe....
* maybe...
*/
{
- int stripe = conf->raid_disks * mddev->chunk_size / PAGE_SIZE;
+ int stripe = conf->raid_disks * (mddev->chunk_size / PAGE_SIZE);
stripe /= conf->near_copies;
if (mddev->queue->backing_dev_info.ra_pages < 2* stripe)
mddev->queue->backing_dev_info.ra_pages = 2* stripe;
git://git.onelab.eu / linux-2.6.git / blobdiff