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path: root/drivers/md/raid5.c
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Diffstat (limited to 'drivers/md/raid5.c')
-rw-r--r--drivers/md/raid5.c252
1 files changed, 178 insertions, 74 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index f351422938e..d26767246d2 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -488,6 +488,27 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
return sh;
}
+/* Determine if 'data_offset' or 'new_data_offset' should be used
+ * in this stripe_head.
+ */
+static int use_new_offset(struct r5conf *conf, struct stripe_head *sh)
+{
+ sector_t progress = conf->reshape_progress;
+ /* Need a memory barrier to make sure we see the value
+ * of conf->generation, or ->data_offset that was set before
+ * reshape_progress was updated.
+ */
+ smp_rmb();
+ if (progress == MaxSector)
+ return 0;
+ if (sh->generation == conf->generation - 1)
+ return 0;
+ /* We are in a reshape, and this is a new-generation stripe,
+ * so use new_data_offset.
+ */
+ return 1;
+}
+
static void
raid5_end_read_request(struct bio *bi, int error);
static void
@@ -518,6 +539,8 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
replace_only = 1;
} else
continue;
+ if (test_and_clear_bit(R5_SyncIO, &sh->dev[i].flags))
+ rw |= REQ_SYNC;
bi = &sh->dev[i].req;
rbi = &sh->dev[i].rreq; /* For writing to replacement */
@@ -603,7 +626,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
__func__, (unsigned long long)sh->sector,
bi->bi_rw, i);
atomic_inc(&sh->count);
- bi->bi_sector = sh->sector + rdev->data_offset;
+ if (use_new_offset(conf, sh))
+ bi->bi_sector = (sh->sector
+ + rdev->new_data_offset);
+ else
+ bi->bi_sector = (sh->sector
+ + rdev->data_offset);
bi->bi_flags = 1 << BIO_UPTODATE;
bi->bi_idx = 0;
bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
@@ -627,7 +655,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
__func__, (unsigned long long)sh->sector,
rbi->bi_rw, i);
atomic_inc(&sh->count);
- rbi->bi_sector = sh->sector + rrdev->data_offset;
+ if (use_new_offset(conf, sh))
+ rbi->bi_sector = (sh->sector
+ + rrdev->new_data_offset);
+ else
+ rbi->bi_sector = (sh->sector
+ + rrdev->data_offset);
rbi->bi_flags = 1 << BIO_UPTODATE;
rbi->bi_idx = 0;
rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
@@ -1114,6 +1147,8 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
dev->sector + STRIPE_SECTORS) {
if (wbi->bi_rw & REQ_FUA)
set_bit(R5_WantFUA, &dev->flags);
+ if (wbi->bi_rw & REQ_SYNC)
+ set_bit(R5_SyncIO, &dev->flags);
tx = async_copy_data(1, wbi, dev->page,
dev->sector, tx);
wbi = r5_next_bio(wbi, dev->sector);
@@ -1131,13 +1166,15 @@ static void ops_complete_reconstruct(void *stripe_head_ref)
int pd_idx = sh->pd_idx;
int qd_idx = sh->qd_idx;
int i;
- bool fua = false;
+ bool fua = false, sync = false;
pr_debug("%s: stripe %llu\n", __func__,
(unsigned long long)sh->sector);
- for (i = disks; i--; )
+ for (i = disks; i--; ) {
fua |= test_bit(R5_WantFUA, &sh->dev[i].flags);
+ sync |= test_bit(R5_SyncIO, &sh->dev[i].flags);
+ }
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
@@ -1146,6 +1183,8 @@ static void ops_complete_reconstruct(void *stripe_head_ref)
set_bit(R5_UPTODATE, &dev->flags);
if (fua)
set_bit(R5_WantFUA, &dev->flags);
+ if (sync)
+ set_bit(R5_SyncIO, &dev->flags);
}
}
@@ -1648,7 +1687,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
char b[BDEVNAME_SIZE];
struct md_rdev *rdev = NULL;
-
+ sector_t s;
for (i=0 ; i<disks; i++)
if (bi == &sh->dev[i].req)
@@ -1671,6 +1710,10 @@ static void raid5_end_read_request(struct bio * bi, int error)
if (!rdev)
rdev = conf->disks[i].rdev;
+ if (use_new_offset(conf, sh))
+ s = sh->sector + rdev->new_data_offset;
+ else
+ s = sh->sector + rdev->data_offset;
if (uptodate) {
set_bit(R5_UPTODATE, &sh->dev[i].flags);
if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
@@ -1683,8 +1726,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
"md/raid:%s: read error corrected"
" (%lu sectors at %llu on %s)\n",
mdname(conf->mddev), STRIPE_SECTORS,
- (unsigned long long)(sh->sector
- + rdev->data_offset),
+ (unsigned long long)s,
bdevname(rdev->bdev, b));
atomic_add(STRIPE_SECTORS, &rdev->corrected_errors);
clear_bit(R5_ReadError, &sh->dev[i].flags);
@@ -1704,8 +1746,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
"md/raid:%s: read error on replacement device "
"(sector %llu on %s).\n",
mdname(conf->mddev),
- (unsigned long long)(sh->sector
- + rdev->data_offset),
+ (unsigned long long)s,
bdn);
else if (conf->mddev->degraded >= conf->max_degraded)
printk_ratelimited(
@@ -1713,8 +1754,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
"md/raid:%s: read error not correctable "
"(sector %llu on %s).\n",
mdname(conf->mddev),
- (unsigned long long)(sh->sector
- + rdev->data_offset),
+ (unsigned long long)s,
bdn);
else if (test_bit(R5_ReWrite, &sh->dev[i].flags))
/* Oh, no!!! */
@@ -1723,8 +1763,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
"md/raid:%s: read error NOT corrected!! "
"(sector %llu on %s).\n",
mdname(conf->mddev),
- (unsigned long long)(sh->sector
- + rdev->data_offset),
+ (unsigned long long)s,
bdn);
else if (atomic_read(&rdev->read_errors)
> conf->max_nr_stripes)
@@ -3561,7 +3600,7 @@ finish:
if (test_and_clear_bit(R5_MadeGood, &dev->flags)) {
rdev = conf->disks[i].rdev;
rdev_clear_badblocks(rdev, sh->sector,
- STRIPE_SECTORS);
+ STRIPE_SECTORS, 0);
rdev_dec_pending(rdev, conf->mddev);
}
if (test_and_clear_bit(R5_MadeGoodRepl, &dev->flags)) {
@@ -3570,7 +3609,7 @@ finish:
/* rdev have been moved down */
rdev = conf->disks[i].rdev;
rdev_clear_badblocks(rdev, sh->sector,
- STRIPE_SECTORS);
+ STRIPE_SECTORS, 0);
rdev_dec_pending(rdev, conf->mddev);
}
}
@@ -3842,6 +3881,7 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
raid_bio->bi_next = (void*)rdev;
align_bi->bi_bdev = rdev->bdev;
align_bi->bi_flags &= ~(1 << BIO_SEG_VALID);
+ /* No reshape active, so we can trust rdev->data_offset */
align_bi->bi_sector += rdev->data_offset;
if (!bio_fits_rdev(align_bi) ||
@@ -3953,12 +3993,10 @@ static void make_request(struct mddev *mddev, struct bio * bi)
plugged = mddev_check_plugged(mddev);
for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
DEFINE_WAIT(w);
- int disks, data_disks;
int previous;
retry:
previous = 0;
- disks = conf->raid_disks;
prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
if (unlikely(conf->reshape_progress != MaxSector)) {
/* spinlock is needed as reshape_progress may be
@@ -3970,13 +4008,12 @@ static void make_request(struct mddev *mddev, struct bio * bi)
* to check again.
*/
spin_lock_irq(&conf->device_lock);
- if (mddev->delta_disks < 0
+ if (mddev->reshape_backwards
? logical_sector < conf->reshape_progress
: logical_sector >= conf->reshape_progress) {
- disks = conf->previous_raid_disks;
previous = 1;
} else {
- if (mddev->delta_disks < 0
+ if (mddev->reshape_backwards
? logical_sector < conf->reshape_safe
: logical_sector >= conf->reshape_safe) {
spin_unlock_irq(&conf->device_lock);
@@ -3986,7 +4023,6 @@ static void make_request(struct mddev *mddev, struct bio * bi)
}
spin_unlock_irq(&conf->device_lock);
}
- data_disks = disks - conf->max_degraded;
new_sector = raid5_compute_sector(conf, logical_sector,
previous,
@@ -4009,7 +4045,7 @@ static void make_request(struct mddev *mddev, struct bio * bi)
*/
int must_retry = 0;
spin_lock_irq(&conf->device_lock);
- if (mddev->delta_disks < 0
+ if (mddev->reshape_backwards
? logical_sector >= conf->reshape_progress
: logical_sector < conf->reshape_progress)
/* mismatch, need to try again */
@@ -4108,11 +4144,11 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
if (sector_nr == 0) {
/* If restarting in the middle, skip the initial sectors */
- if (mddev->delta_disks < 0 &&
+ if (mddev->reshape_backwards &&
conf->reshape_progress < raid5_size(mddev, 0, 0)) {
sector_nr = raid5_size(mddev, 0, 0)
- conf->reshape_progress;
- } else if (mddev->delta_disks >= 0 &&
+ } else if (!mddev->reshape_backwards &&
conf->reshape_progress > 0)
sector_nr = conf->reshape_progress;
sector_div(sector_nr, new_data_disks);
@@ -4133,13 +4169,11 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
else
reshape_sectors = mddev->chunk_sectors;
- /* we update the metadata when there is more than 3Meg
- * in the block range (that is rather arbitrary, should
- * probably be time based) or when the data about to be
- * copied would over-write the source of the data at
- * the front of the range.
- * i.e. one new_stripe along from reshape_progress new_maps
- * to after where reshape_safe old_maps to
+ /* We update the metadata at least every 10 seconds, or when
+ * the data about to be copied would over-write the source of
+ * the data at the front of the range. i.e. one new_stripe
+ * along from reshape_progress new_maps to after where
+ * reshape_safe old_maps to
*/
writepos = conf->reshape_progress;
sector_div(writepos, new_data_disks);
@@ -4147,7 +4181,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
sector_div(readpos, data_disks);
safepos = conf->reshape_safe;
sector_div(safepos, data_disks);
- if (mddev->delta_disks < 0) {
+ if (mddev->reshape_backwards) {
writepos -= min_t(sector_t, reshape_sectors, writepos);
readpos += reshape_sectors;
safepos += reshape_sectors;
@@ -4157,11 +4191,29 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
safepos -= min_t(sector_t, reshape_sectors, safepos);
}
+ /* Having calculated the 'writepos' possibly use it
+ * to set 'stripe_addr' which is where we will write to.
+ */
+ if (mddev->reshape_backwards) {
+ BUG_ON(conf->reshape_progress == 0);
+ stripe_addr = writepos;
+ BUG_ON((mddev->dev_sectors &
+ ~((sector_t)reshape_sectors - 1))
+ - reshape_sectors - stripe_addr
+ != sector_nr);
+ } else {
+ BUG_ON(writepos != sector_nr + reshape_sectors);
+ stripe_addr = sector_nr;
+ }
+
/* 'writepos' is the most advanced device address we might write.
* 'readpos' is the least advanced device address we might read.
* 'safepos' is the least address recorded in the metadata as having
* been reshaped.
- * If 'readpos' is behind 'writepos', then there is no way that we can
+ * If there is a min_offset_diff, these are adjusted either by
+ * increasing the safepos/readpos if diff is negative, or
+ * increasing writepos if diff is positive.
+ * If 'readpos' is then behind 'writepos', there is no way that we can
* ensure safety in the face of a crash - that must be done by userspace
* making a backup of the data. So in that case there is no particular
* rush to update metadata.
@@ -4174,7 +4226,13 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
* Maybe that number should be configurable, but I'm not sure it is
* worth it.... maybe it could be a multiple of safemode_delay???
*/
- if ((mddev->delta_disks < 0
+ if (conf->min_offset_diff < 0) {
+ safepos += -conf->min_offset_diff;
+ readpos += -conf->min_offset_diff;
+ } else
+ writepos += conf->min_offset_diff;
+
+ if ((mddev->reshape_backwards
? (safepos > writepos && readpos < writepos)
: (safepos < writepos && readpos > writepos)) ||
time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
@@ -4195,17 +4253,6 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
sysfs_notify(&mddev->kobj, NULL, "sync_completed");
}
- if (mddev->delta_disks < 0) {
- BUG_ON(conf->reshape_progress == 0);
- stripe_addr = writepos;
- BUG_ON((mddev->dev_sectors &
- ~((sector_t)reshape_sectors - 1))
- - reshape_sectors - stripe_addr
- != sector_nr);
- } else {
- BUG_ON(writepos != sector_nr + reshape_sectors);
- stripe_addr = sector_nr;
- }
INIT_LIST_HEAD(&stripes);
for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
int j;
@@ -4239,7 +4286,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
list_add(&sh->lru, &stripes);
}
spin_lock_irq(&conf->device_lock);
- if (mddev->delta_disks < 0)
+ if (mddev->reshape_backwards)
conf->reshape_progress -= reshape_sectors * new_data_disks;
else
conf->reshape_progress += reshape_sectors * new_data_disks;
@@ -4952,16 +4999,42 @@ static int run(struct mddev *mddev)
struct md_rdev *rdev;
sector_t reshape_offset = 0;
int i;
+ long long min_offset_diff = 0;
+ int first = 1;
if (mddev->recovery_cp != MaxSector)
printk(KERN_NOTICE "md/raid:%s: not clean"
" -- starting background reconstruction\n",
mdname(mddev));
+
+ rdev_for_each(rdev, mddev) {
+ long long diff;
+ if (rdev->raid_disk < 0)
+ continue;
+ diff = (rdev->new_data_offset - rdev->data_offset);
+ if (first) {
+ min_offset_diff = diff;
+ first = 0;
+ } else if (mddev->reshape_backwards &&
+ diff < min_offset_diff)
+ min_offset_diff = diff;
+ else if (!mddev->reshape_backwards &&
+ diff > min_offset_diff)
+ min_offset_diff = diff;
+ }
+
if (mddev->reshape_position != MaxSector) {
/* Check that we can continue the reshape.
- * Currently only disks can change, it must
- * increase, and we must be past the point where
- * a stripe over-writes itself
+ * Difficulties arise if the stripe we would write to
+ * next is at or after the stripe we would read from next.
+ * For a reshape that changes the number of devices, this
+ * is only possible for a very short time, and mdadm makes
+ * sure that time appears to have past before assembling
+ * the array. So we fail if that time hasn't passed.
+ * For a reshape that keeps the number of devices the same
+ * mdadm must be monitoring the reshape can keeping the
+ * critical areas read-only and backed up. It will start
+ * the array in read-only mode, so we check for that.
*/
sector_t here_new, here_old;
int old_disks;
@@ -4993,26 +5066,34 @@ static int run(struct mddev *mddev)
/* here_old is the first stripe that we might need to read
* from */
if (mddev->delta_disks == 0) {
+ if ((here_new * mddev->new_chunk_sectors !=
+ here_old * mddev->chunk_sectors)) {
+ printk(KERN_ERR "md/raid:%s: reshape position is"
+ " confused - aborting\n", mdname(mddev));
+ return -EINVAL;
+ }
/* We cannot be sure it is safe to start an in-place
- * reshape. It is only safe if user-space if monitoring
+ * reshape. It is only safe if user-space is monitoring
* and taking constant backups.
* mdadm always starts a situation like this in
* readonly mode so it can take control before
* allowing any writes. So just check for that.
*/
- if ((here_new * mddev->new_chunk_sectors !=
- here_old * mddev->chunk_sectors) ||
- mddev->ro == 0) {
- printk(KERN_ERR "md/raid:%s: in-place reshape must be started"
- " in read-only mode - aborting\n",
+ if (abs(min_offset_diff) >= mddev->chunk_sectors &&
+ abs(min_offset_diff) >= mddev->new_chunk_sectors)
+ /* not really in-place - so OK */;
+ else if (mddev->ro == 0) {
+ printk(KERN_ERR "md/raid:%s: in-place reshape "
+ "must be started in read-only mode "
+ "- aborting\n",
mdname(mddev));
return -EINVAL;
}
- } else if (mddev->delta_disks < 0
- ? (here_new * mddev->new_chunk_sectors <=
+ } else if (mddev->reshape_backwards
+ ? (here_new * mddev->new_chunk_sectors + min_offset_diff <=
here_old * mddev->chunk_sectors)
: (here_new * mddev->new_chunk_sectors >=
- here_old * mddev->chunk_sectors)) {
+ here_old * mddev->chunk_sectors + (-min_offset_diff))) {
/* Reading from the same stripe as writing to - bad */
printk(KERN_ERR "md/raid:%s: reshape_position too early for "
"auto-recovery - aborting.\n",
@@ -5037,6 +5118,7 @@ static int run(struct mddev *mddev)
if (IS_ERR(conf))
return PTR_ERR(conf);
+ conf->min_offset_diff = min_offset_diff;
mddev->thread = conf->thread;
conf->thread = NULL;
mddev->private = conf;
@@ -5182,9 +5264,12 @@ static int run(struct mddev *mddev)
blk_queue_io_opt(mddev->queue, chunk_size *
(conf->raid_disks - conf->max_degraded));
- rdev_for_each(rdev, mddev)
+ rdev_for_each(rdev, mddev) {
disk_stack_limits(mddev->gendisk, rdev->bdev,
rdev->data_offset << 9);
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->new_data_offset << 9);
+ }
}
return 0;
@@ -5418,12 +5503,18 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
* any io in the removed space completes, but it hardly seems
* worth it.
*/
+ sector_t newsize;
sectors &= ~((sector_t)mddev->chunk_sectors - 1);
- md_set_array_sectors(mddev, raid5_size(mddev, sectors,
- mddev->raid_disks));
- if (mddev->array_sectors >
- raid5_size(mddev, sectors, mddev->raid_disks))
+ newsize = raid5_size(mddev, sectors, mddev->raid_disks);
+ if (mddev->external_size &&
+ mddev->array_sectors > newsize)
return -EINVAL;
+ if (mddev->bitmap) {
+ int ret = bitmap_resize(mddev->bitmap, sectors, 0, 0);
+ if (ret)
+ return ret;
+ }
+ md_set_array_sectors(mddev, newsize);
set_capacity(mddev->gendisk, mddev->array_sectors);
revalidate_disk(mddev->gendisk);
if (sectors > mddev->dev_sectors &&
@@ -5468,9 +5559,6 @@ static int check_reshape(struct mddev *mddev)
mddev->new_layout == mddev->layout &&
mddev->new_chunk_sectors == mddev->chunk_sectors)
return 0; /* nothing to do */
- if (mddev->bitmap)
- /* Cannot grow a bitmap yet */
- return -EBUSY;
if (has_failed(conf))
return -EINVAL;
if (mddev->delta_disks < 0) {
@@ -5505,10 +5593,14 @@ static int raid5_start_reshape(struct mddev *mddev)
if (!check_stripe_cache(mddev))
return -ENOSPC;
- rdev_for_each(rdev, mddev)
+ if (has_failed(conf))
+ return -EINVAL;
+
+ rdev_for_each(rdev, mddev) {
if (!test_bit(In_sync, &rdev->flags)
&& !test_bit(Faulty, &rdev->flags))
spares++;
+ }
if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded)
/* Not enough devices even to make a degraded array
@@ -5535,12 +5627,16 @@ static int raid5_start_reshape(struct mddev *mddev)
conf->chunk_sectors = mddev->new_chunk_sectors;
conf->prev_algo = conf->algorithm;
conf->algorithm = mddev->new_layout;
- if (mddev->delta_disks < 0)
+ conf->generation++;
+ /* Code that selects data_offset needs to see the generation update
+ * if reshape_progress has been set - so a memory barrier needed.
+ */
+ smp_mb();
+ if (mddev->reshape_backwards)
conf->reshape_progress = raid5_size(mddev, 0, 0);
else
conf->reshape_progress = 0;
conf->reshape_safe = conf->reshape_progress;
- conf->generation++;
spin_unlock_irq(&conf->device_lock);
/* Add some new drives, as many as will fit.
@@ -5592,6 +5688,9 @@ static int raid5_start_reshape(struct mddev *mddev)
mddev->recovery = 0;
spin_lock_irq(&conf->device_lock);
mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks;
+ rdev_for_each(rdev, mddev)
+ rdev->new_data_offset = rdev->data_offset;
+ smp_wmb();
conf->reshape_progress = MaxSector;
mddev->reshape_position = MaxSector;
spin_unlock_irq(&conf->device_lock);
@@ -5610,9 +5709,13 @@ static void end_reshape(struct r5conf *conf)
{
if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
+ struct md_rdev *rdev;
spin_lock_irq(&conf->device_lock);
conf->previous_raid_disks = conf->raid_disks;
+ rdev_for_each(rdev, conf->mddev)
+ rdev->data_offset = rdev->new_data_offset;
+ smp_wmb();
conf->reshape_progress = MaxSector;
spin_unlock_irq(&conf->device_lock);
wake_up(&conf->wait_for_overlap);
@@ -5652,17 +5755,18 @@ static void raid5_finish_reshape(struct mddev *mddev)
d < conf->raid_disks - mddev->delta_disks;
d++) {
struct md_rdev *rdev = conf->disks[d].rdev;
- if (rdev &&
- raid5_remove_disk(mddev, rdev) == 0) {
- sysfs_unlink_rdev(mddev, rdev);
- rdev->raid_disk = -1;
- }
+ if (rdev)
+ clear_bit(In_sync, &rdev->flags);
+ rdev = conf->disks[d].replacement;
+ if (rdev)
+ clear_bit(In_sync, &rdev->flags);
}
}
mddev->layout = conf->algorithm;
mddev->chunk_sectors = conf->chunk_sectors;
mddev->reshape_position = MaxSector;
mddev->delta_disks = 0;
+ mddev->reshape_backwards = 0;
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-13 22:05:24 +0000