#include <linux/raid/raid5.h>
#include <linux/highmem.h>
#include <linux/bitops.h>
+#include <linux/kthread.h>
#include <asm/atomic.h>
#include <linux/raid/bitmap.h>
static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh)
{
if (atomic_dec_and_test(&sh->count)) {
- if (!list_empty(&sh->lru))
- BUG();
- if (atomic_read(&conf->active_stripes)==0)
- BUG();
+ BUG_ON(!list_empty(&sh->lru));
+ BUG_ON(atomic_read(&conf->active_stripes)==0);
if (test_bit(STRIPE_HANDLE, &sh->state)) {
if (test_bit(STRIPE_DELAYED, &sh->state))
list_add_tail(&sh->lru, &conf->delayed_list);
if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD)
md_wakeup_thread(conf->mddev->thread);
}
- list_add_tail(&sh->lru, &conf->inactive_list);
atomic_dec(&conf->active_stripes);
- if (!conf->inactive_blocked ||
- atomic_read(&conf->active_stripes) < (conf->max_nr_stripes*3/4))
+ if (!test_bit(STRIPE_EXPANDING, &sh->state)) {
+ list_add_tail(&sh->lru, &conf->inactive_list);
wake_up(&conf->wait_for_stripe);
+ }
}
}
}
static void raid5_build_block (struct stripe_head *sh, int i);
-static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx)
+static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx, int disks)
{
raid5_conf_t *conf = sh->raid_conf;
- int disks = conf->raid_disks, i;
+ int i;
- if (atomic_read(&sh->count) != 0)
- BUG();
- if (test_bit(STRIPE_HANDLE, &sh->state))
- BUG();
+ BUG_ON(atomic_read(&sh->count) != 0);
+ BUG_ON(test_bit(STRIPE_HANDLE, &sh->state));
CHECK_DEVLOCK();
PRINTK("init_stripe called, stripe %llu\n",
sh->pd_idx = pd_idx;
sh->state = 0;
- for (i=disks; i--; ) {
+ sh->disks = disks;
+
+ for (i = sh->disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
if (dev->toread || dev->towrite || dev->written ||
insert_hash(conf, sh);
}
-static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector)
+static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks)
{
struct stripe_head *sh;
struct hlist_node *hn;
CHECK_DEVLOCK();
PRINTK("__find_stripe, sector %llu\n", (unsigned long long)sector);
hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash)
- if (sh->sector == sector)
+ if (sh->sector == sector && sh->disks == disks)
return sh;
PRINTK("__stripe %llu not in cache\n", (unsigned long long)sector);
return NULL;
static void unplug_slaves(mddev_t *mddev);
static void raid5_unplug_device(request_queue_t *q);
-static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector,
- int pd_idx, int noblock)
+static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector, int disks,
+ int pd_idx, int noblock)
{
struct stripe_head *sh;
wait_event_lock_irq(conf->wait_for_stripe,
conf->quiesce == 0,
conf->device_lock, /* nothing */);
- sh = __find_stripe(conf, sector);
+ sh = __find_stripe(conf, sector, disks);
if (!sh) {
if (!conf->inactive_blocked)
sh = get_free_stripe(conf);
< (conf->max_nr_stripes *3/4)
|| !conf->inactive_blocked),
conf->device_lock,
- unplug_slaves(conf->mddev);
+ unplug_slaves(conf->mddev)
);
conf->inactive_blocked = 0;
} else
- init_stripe(sh, sector, pd_idx);
+ init_stripe(sh, sector, pd_idx, disks);
} else {
if (atomic_read(&sh->count)) {
- if (!list_empty(&sh->lru))
- BUG();
+ BUG_ON(!list_empty(&sh->lru));
} else {
if (!test_bit(STRIPE_HANDLE, &sh->state))
atomic_inc(&conf->active_stripes);
- if (list_empty(&sh->lru))
- BUG();
- list_del_init(&sh->lru);
+ if (!list_empty(&sh->lru))
+ list_del_init(&sh->lru);
}
}
} while (sh == NULL);
kmem_cache_free(conf->slab_cache, sh);
return 0;
}
+ sh->disks = conf->raid_disks;
/* we just created an active stripe so... */
atomic_set(&sh->count, 1);
atomic_inc(&conf->active_stripes);
kmem_cache_t *sc;
int devs = conf->raid_disks;
- sprintf(conf->cache_name, "raid5/%s", mdname(conf->mddev));
-
- sc = kmem_cache_create(conf->cache_name,
+ sprintf(conf->cache_name[0], "raid5/%s", mdname(conf->mddev));
+ sprintf(conf->cache_name[1], "raid5/%s-alt", mdname(conf->mddev));
+ conf->active_name = 0;
+ sc = kmem_cache_create(conf->cache_name[conf->active_name],
sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
0, 0, NULL, NULL);
if (!sc)
return 1;
conf->slab_cache = sc;
+ conf->pool_size = devs;
while (num--) {
if (!grow_one_stripe(conf))
return 1;
return 0;
}
+#ifdef CONFIG_MD_RAID5_RESHAPE
+static int resize_stripes(raid5_conf_t *conf, int newsize)
+{
+ /* Make all the stripes able to hold 'newsize' devices.
+ * New slots in each stripe get 'page' set to a new page.
+ *
+ * This happens in stages:
+ * 1/ create a new kmem_cache and allocate the required number of
+ * stripe_heads.
+ * 2/ gather all the old stripe_heads and tranfer the pages across
+ * to the new stripe_heads. This will have the side effect of
+ * freezing the array as once all stripe_heads have been collected,
+ * no IO will be possible. Old stripe heads are freed once their
+ * pages have been transferred over, and the old kmem_cache is
+ * freed when all stripes are done.
+ * 3/ reallocate conf->disks to be suitable bigger. If this fails,
+ * we simple return a failre status - no need to clean anything up.
+ * 4/ allocate new pages for the new slots in the new stripe_heads.
+ * If this fails, we don't bother trying the shrink the
+ * stripe_heads down again, we just leave them as they are.
+ * As each stripe_head is processed the new one is released into
+ * active service.
+ *
+ * Once step2 is started, we cannot afford to wait for a write,
+ * so we use GFP_NOIO allocations.
+ */
+ struct stripe_head *osh, *nsh;
+ LIST_HEAD(newstripes);
+ struct disk_info *ndisks;
+ int err = 0;
+ kmem_cache_t *sc;
+ int i;
+
+ if (newsize <= conf->pool_size)
+ return 0; /* never bother to shrink */
+
+ /* Step 1 */
+ sc = kmem_cache_create(conf->cache_name[1-conf->active_name],
+ sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev),
+ 0, 0, NULL, NULL);
+ if (!sc)
+ return -ENOMEM;
+
+ for (i = conf->max_nr_stripes; i; i--) {
+ nsh = kmem_cache_alloc(sc, GFP_KERNEL);
+ if (!nsh)
+ break;
+
+ memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev));
+
+ nsh->raid_conf = conf;
+ spin_lock_init(&nsh->lock);
+
+ list_add(&nsh->lru, &newstripes);
+ }
+ if (i) {
+ /* didn't get enough, give up */
+ while (!list_empty(&newstripes)) {
+ nsh = list_entry(newstripes.next, struct stripe_head, lru);
+ list_del(&nsh->lru);
+ kmem_cache_free(sc, nsh);
+ }
+ kmem_cache_destroy(sc);
+ return -ENOMEM;
+ }
+ /* Step 2 - Must use GFP_NOIO now.
+ * OK, we have enough stripes, start collecting inactive
+ * stripes and copying them over
+ */
+ list_for_each_entry(nsh, &newstripes, lru) {
+ spin_lock_irq(&conf->device_lock);
+ wait_event_lock_irq(conf->wait_for_stripe,
+ !list_empty(&conf->inactive_list),
+ conf->device_lock,
+ unplug_slaves(conf->mddev)
+ );
+ osh = get_free_stripe(conf);
+ spin_unlock_irq(&conf->device_lock);
+ atomic_set(&nsh->count, 1);
+ for(i=0; i<conf->pool_size; i++)
+ nsh->dev[i].page = osh->dev[i].page;
+ for( ; i<newsize; i++)
+ nsh->dev[i].page = NULL;
+ kmem_cache_free(conf->slab_cache, osh);
+ }
+ kmem_cache_destroy(conf->slab_cache);
+
+ /* Step 3.
+ * At this point, we are holding all the stripes so the array
+ * is completely stalled, so now is a good time to resize
+ * conf->disks.
+ */
+ ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO);
+ if (ndisks) {
+ for (i=0; i<conf->raid_disks; i++)
+ ndisks[i] = conf->disks[i];
+ kfree(conf->disks);
+ conf->disks = ndisks;
+ } else
+ err = -ENOMEM;
+
+ /* Step 4, return new stripes to service */
+ while(!list_empty(&newstripes)) {
+ nsh = list_entry(newstripes.next, struct stripe_head, lru);
+ list_del_init(&nsh->lru);
+ for (i=conf->raid_disks; i < newsize; i++)
+ if (nsh->dev[i].page == NULL) {
+ struct page *p = alloc_page(GFP_NOIO);
+ nsh->dev[i].page = p;
+ if (!p)
+ err = -ENOMEM;
+ }
+ release_stripe(nsh);
+ }
+ /* critical section pass, GFP_NOIO no longer needed */
+
+ conf->slab_cache = sc;
+ conf->active_name = 1-conf->active_name;
+ conf->pool_size = newsize;
+ return err;
+}
+#endif
+
static int drop_one_stripe(raid5_conf_t *conf)
{
struct stripe_head *sh;
spin_unlock_irq(&conf->device_lock);
if (!sh)
return 0;
- if (atomic_read(&sh->count))
- BUG();
- shrink_buffers(sh, conf->raid_disks);
+ BUG_ON(atomic_read(&sh->count));
+ shrink_buffers(sh, conf->pool_size);
kmem_cache_free(conf->slab_cache, sh);
atomic_dec(&conf->active_stripes);
return 1;
{
struct stripe_head *sh = bi->bi_private;
raid5_conf_t *conf = sh->raid_conf;
- int disks = conf->raid_disks, i;
+ int disks = sh->disks, i;
int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
if (bi->bi_size)
{
struct stripe_head *sh = bi->bi_private;
raid5_conf_t *conf = sh->raid_conf;
- int disks = conf->raid_disks, i;
+ int disks = sh->disks, i;
unsigned long flags;
int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
static sector_t compute_blocknr(struct stripe_head *sh, int i)
{
raid5_conf_t *conf = sh->raid_conf;
- int raid_disks = conf->raid_disks, data_disks = raid_disks - 1;
+ int raid_disks = sh->disks, data_disks = raid_disks - 1;
sector_t new_sector = sh->sector, check;
int sectors_per_chunk = conf->chunk_size >> 9;
sector_t stripe;
static void compute_block(struct stripe_head *sh, int dd_idx)
{
- raid5_conf_t *conf = sh->raid_conf;
- int i, count, disks = conf->raid_disks;
+ int i, count, disks = sh->disks;
void *ptr[MAX_XOR_BLOCKS], *p;
PRINTK("compute_block, stripe %llu, idx %d\n",
static void compute_parity(struct stripe_head *sh, int method)
{
raid5_conf_t *conf = sh->raid_conf;
- int i, pd_idx = sh->pd_idx, disks = conf->raid_disks, count;
+ int i, pd_idx = sh->pd_idx, disks = sh->disks, count;
void *ptr[MAX_XOR_BLOCKS];
struct bio *chosen;
ptr[0] = page_address(sh->dev[pd_idx].page);
switch(method) {
case READ_MODIFY_WRITE:
- if (!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags))
- BUG();
+ BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags));
for (i=disks ; i-- ;) {
if (i==pd_idx)
continue;
if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
wake_up(&conf->wait_for_overlap);
- if (sh->dev[i].written) BUG();
+ BUG_ON(sh->dev[i].written);
sh->dev[i].written = chosen;
check_xor();
}
if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
wake_up(&conf->wait_for_overlap);
- if (sh->dev[i].written) BUG();
+ BUG_ON(sh->dev[i].written);
sh->dev[i].written = chosen;
}
break;
if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9))
goto overlap;
- if (*bip && bi->bi_next && (*bip) != bi->bi_next)
- BUG();
+ BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next);
if (*bip)
bi->bi_next = *bip;
*bip = bi;
return 0;
}
+static void end_reshape(raid5_conf_t *conf);
+
+static int stripe_to_pdidx(sector_t stripe, raid5_conf_t *conf, int disks)
+{
+ int sectors_per_chunk = conf->chunk_size >> 9;
+ sector_t x = stripe;
+ int pd_idx, dd_idx;
+ int chunk_offset = sector_div(x, sectors_per_chunk);
+ stripe = x;
+ raid5_compute_sector(stripe*(disks-1)*sectors_per_chunk
+ + chunk_offset, disks, disks-1, &dd_idx, &pd_idx, conf);
+ return pd_idx;
+}
+
/*
* handle_stripe - do things to a stripe.
static void handle_stripe(struct stripe_head *sh)
{
raid5_conf_t *conf = sh->raid_conf;
- int disks = conf->raid_disks;
+ int disks = sh->disks;
struct bio *return_bi= NULL;
struct bio *bi;
int i;
- int syncing;
+ int syncing, expanding, expanded;
int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0;
int non_overwrite = 0;
int failed_num=0;
clear_bit(STRIPE_DELAYED, &sh->state);
syncing = test_bit(STRIPE_SYNCING, &sh->state);
+ expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state);
+ expanded = test_bit(STRIPE_EXPAND_READY, &sh->state);
/* Now to look around and see what can be done */
rcu_read_lock();
* parity, or to satisfy requests
* or to load a block that is being partially written.
*/
- if (to_read || non_overwrite || (syncing && (uptodate < disks))) {
+ if (to_read || non_overwrite || (syncing && (uptodate < disks)) || expanding) {
for (i=disks; i--;) {
dev = &sh->dev[i];
if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) &&
(dev->toread ||
(dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
syncing ||
+ expanding ||
(failed && (sh->dev[failed_num].toread ||
(sh->dev[failed_num].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num].flags))))
)
set_bit(STRIPE_HANDLE, &sh->state);
if (failed == 0) {
char *pagea;
- if (uptodate != disks)
- BUG();
+ BUG_ON(uptodate != disks);
compute_parity(sh, CHECK_PARITY);
uptodate--;
pagea = page_address(sh->dev[sh->pd_idx].page);
set_bit(R5_Wantwrite, &dev->flags);
set_bit(R5_ReWrite, &dev->flags);
set_bit(R5_LOCKED, &dev->flags);
+ locked++;
} else {
/* let's read it back */
set_bit(R5_Wantread, &dev->flags);
set_bit(R5_LOCKED, &dev->flags);
+ locked++;
}
}
+ if (expanded && test_bit(STRIPE_EXPANDING, &sh->state)) {
+ /* Need to write out all blocks after computing parity */
+ sh->disks = conf->raid_disks;
+ sh->pd_idx = stripe_to_pdidx(sh->sector, conf, conf->raid_disks);
+ compute_parity(sh, RECONSTRUCT_WRITE);
+ for (i= conf->raid_disks; i--;) {
+ set_bit(R5_LOCKED, &sh->dev[i].flags);
+ locked++;
+ set_bit(R5_Wantwrite, &sh->dev[i].flags);
+ }
+ clear_bit(STRIPE_EXPANDING, &sh->state);
+ } else if (expanded) {
+ clear_bit(STRIPE_EXPAND_READY, &sh->state);
+ atomic_dec(&conf->reshape_stripes);
+ wake_up(&conf->wait_for_overlap);
+ md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
+ }
+
+ if (expanding && locked == 0) {
+ /* We have read all the blocks in this stripe and now we need to
+ * copy some of them into a target stripe for expand.
+ */
+ clear_bit(STRIPE_EXPAND_SOURCE, &sh->state);
+ for (i=0; i< sh->disks; i++)
+ if (i != sh->pd_idx) {
+ int dd_idx, pd_idx, j;
+ struct stripe_head *sh2;
+
+ sector_t bn = compute_blocknr(sh, i);
+ sector_t s = raid5_compute_sector(bn, conf->raid_disks,
+ conf->raid_disks-1,
+ &dd_idx, &pd_idx, conf);
+ sh2 = get_active_stripe(conf, s, conf->raid_disks, pd_idx, 1);
+ if (sh2 == NULL)
+ /* so far only the early blocks of this stripe
+ * have been requested. When later blocks
+ * get requested, we will try again
+ */
+ continue;
+ if(!test_bit(STRIPE_EXPANDING, &sh2->state) ||
+ test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) {
+ /* must have already done this block */
+ release_stripe(sh2);
+ continue;
+ }
+ memcpy(page_address(sh2->dev[dd_idx].page),
+ page_address(sh->dev[i].page),
+ STRIPE_SIZE);
+ set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
+ set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags);
+ for (j=0; j<conf->raid_disks; j++)
+ if (j != sh2->pd_idx &&
+ !test_bit(R5_Expanded, &sh2->dev[j].flags))
+ break;
+ if (j == conf->raid_disks) {
+ set_bit(STRIPE_EXPAND_READY, &sh2->state);
+ set_bit(STRIPE_HANDLE, &sh2->state);
+ }
+ release_stripe(sh2);
+ }
+ }
+
spin_unlock(&sh->lock);
while ((bi=return_bi)) {
rcu_read_unlock();
if (rdev) {
- if (syncing)
+ if (syncing || expanding || expanded)
md_sync_acct(rdev->bdev, STRIPE_SECTORS);
bi->bi_bdev = rdev->bdev;
spin_unlock_irq(&conf->device_lock);
}
-static int make_request (request_queue_t *q, struct bio * bi)
+static int make_request(request_queue_t *q, struct bio * bi)
{
mddev_t *mddev = q->queuedata;
raid5_conf_t *conf = mddev_to_conf(mddev);
- const unsigned int raid_disks = conf->raid_disks;
- const unsigned int data_disks = raid_disks - 1;
unsigned int dd_idx, pd_idx;
sector_t new_sector;
sector_t logical_sector, last_sector;
struct stripe_head *sh;
const int rw = bio_data_dir(bi);
+ int remaining;
if (unlikely(bio_barrier(bi))) {
bio_endio(bi, bi->bi_size, -EOPNOTSUPP);
for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
DEFINE_WAIT(w);
-
- new_sector = raid5_compute_sector(logical_sector,
- raid_disks, data_disks, &dd_idx, &pd_idx, conf);
+ int disks;
+ retry:
+ prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
+ if (likely(conf->expand_progress == MaxSector))
+ disks = conf->raid_disks;
+ else {
+ /* spinlock is needed as expand_progress may be
+ * 64bit on a 32bit platform, and so it might be
+ * possible to see a half-updated value
+ * Ofcourse expand_progress could change after
+ * the lock is dropped, so once we get a reference
+ * to the stripe that we think it is, we will have
+ * to check again.
+ */
+ spin_lock_irq(&conf->device_lock);
+ disks = conf->raid_disks;
+ if (logical_sector >= conf->expand_progress)
+ disks = conf->previous_raid_disks;
+ else {
+ if (logical_sector >= conf->expand_lo) {
+ spin_unlock_irq(&conf->device_lock);
+ schedule();
+ goto retry;
+ }
+ }
+ spin_unlock_irq(&conf->device_lock);
+ }
+ new_sector = raid5_compute_sector(logical_sector, disks, disks - 1,
+ &dd_idx, &pd_idx, conf);
PRINTK("raid5: make_request, sector %llu logical %llu\n",
(unsigned long long)new_sector,
(unsigned long long)logical_sector);
- retry:
- prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
- sh = get_active_stripe(conf, new_sector, pd_idx, (bi->bi_rw&RWA_MASK));
+ sh = get_active_stripe(conf, new_sector, disks, pd_idx, (bi->bi_rw&RWA_MASK));
if (sh) {
- if (!add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) {
- /* Add failed due to overlap. Flush everything
+ if (unlikely(conf->expand_progress != MaxSector)) {
+ /* expansion might have moved on while waiting for a
+ * stripe, so we must do the range check again.
+ * Expansion could still move past after this
+ * test, but as we are holding a reference to
+ * 'sh', we know that if that happens,
+ * STRIPE_EXPANDING will get set and the expansion
+ * won't proceed until we finish with the stripe.
+ */
+ int must_retry = 0;
+ spin_lock_irq(&conf->device_lock);
+ if (logical_sector < conf->expand_progress &&
+ disks == conf->previous_raid_disks)
+ /* mismatch, need to try again */
+ must_retry = 1;
+ spin_unlock_irq(&conf->device_lock);
+ if (must_retry) {
+ release_stripe(sh);
+ goto retry;
+ }
+ }
+ /* FIXME what if we get a false positive because these
+ * are being updated.
+ */
+ if (logical_sector >= mddev->suspend_lo &&
+ logical_sector < mddev->suspend_hi) {
+ release_stripe(sh);
+ schedule();
+ goto retry;
+ }
+
+ if (test_bit(STRIPE_EXPANDING, &sh->state) ||
+ !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) {
+ /* Stripe is busy expanding or
+ * add failed due to overlap. Flush everything
* and wait a while
*/
raid5_unplug_device(mddev->queue);
raid5_plug_device(conf);
handle_stripe(sh);
release_stripe(sh);
-
} else {
/* cannot get stripe for read-ahead, just give-up */
clear_bit(BIO_UPTODATE, &bi->bi_flags);
}
spin_lock_irq(&conf->device_lock);
- if (--bi->bi_phys_segments == 0) {
+ remaining = --bi->bi_phys_segments;
+ spin_unlock_irq(&conf->device_lock);
+ if (remaining == 0) {
int bytes = bi->bi_size;
if ( bio_data_dir(bi) == WRITE )
bi->bi_size = 0;
bi->bi_end_io(bi, bytes, 0);
}
- spin_unlock_irq(&conf->device_lock);
return 0;
}
{
raid5_conf_t *conf = (raid5_conf_t *) mddev->private;
struct stripe_head *sh;
- int sectors_per_chunk = conf->chunk_size >> 9;
- sector_t x;
- unsigned long stripe;
- int chunk_offset;
- int dd_idx, pd_idx;
- sector_t first_sector;
+ int pd_idx;
+ sector_t first_sector, last_sector;
int raid_disks = conf->raid_disks;
int data_disks = raid_disks-1;
sector_t max_sector = mddev->size << 1;
if (sector_nr >= max_sector) {
/* just being told to finish up .. nothing much to do */
unplug_slaves(mddev);
+ if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
+ end_reshape(conf);
+ return 0;
+ }
if (mddev->curr_resync < max_sector) /* aborted */
bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
return 0;
}
+
+ if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
+ /* reshaping is quite different to recovery/resync so it is
+ * handled quite separately ... here.
+ *
+ * On each call to sync_request, we gather one chunk worth of
+ * destination stripes and flag them as expanding.
+ * Then we find all the source stripes and request reads.
+ * As the reads complete, handle_stripe will copy the data
+ * into the destination stripe and release that stripe.
+ */
+ int i;
+ int dd_idx;
+ sector_t writepos, safepos, gap;
+
+ if (sector_nr == 0 &&
+ conf->expand_progress != 0) {
+ /* restarting in the middle, skip the initial sectors */
+ sector_nr = conf->expand_progress;
+ sector_div(sector_nr, conf->raid_disks-1);
+ *skipped = 1;
+ return sector_nr;
+ }
+
+ /* 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 forward from expand_progress new_maps
+ * to after where expand_lo old_maps to
+ */
+ writepos = conf->expand_progress +
+ conf->chunk_size/512*(conf->raid_disks-1);
+ sector_div(writepos, conf->raid_disks-1);
+ safepos = conf->expand_lo;
+ sector_div(safepos, conf->previous_raid_disks-1);
+ gap = conf->expand_progress - conf->expand_lo;
+
+ if (writepos >= safepos ||
+ gap > (conf->raid_disks-1)*3000*2 /*3Meg*/) {
+ /* Cannot proceed until we've updated the superblock... */
+ wait_event(conf->wait_for_overlap,
+ atomic_read(&conf->reshape_stripes)==0);
+ mddev->reshape_position = conf->expand_progress;
+ mddev->sb_dirty = 1;
+ md_wakeup_thread(mddev->thread);
+ wait_event(mddev->sb_wait, mddev->sb_dirty == 0 ||
+ kthread_should_stop());
+ spin_lock_irq(&conf->device_lock);
+ conf->expand_lo = mddev->reshape_position;
+ spin_unlock_irq(&conf->device_lock);
+ wake_up(&conf->wait_for_overlap);
+ }
+
+ for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) {
+ int j;
+ int skipped = 0;
+ pd_idx = stripe_to_pdidx(sector_nr+i, conf, conf->raid_disks);
+ sh = get_active_stripe(conf, sector_nr+i,
+ conf->raid_disks, pd_idx, 0);
+ set_bit(STRIPE_EXPANDING, &sh->state);
+ atomic_inc(&conf->reshape_stripes);
+ /* If any of this stripe is beyond the end of the old
+ * array, then we need to zero those blocks
+ */
+ for (j=sh->disks; j--;) {
+ sector_t s;
+ if (j == sh->pd_idx)
+ continue;
+ s = compute_blocknr(sh, j);
+ if (s < (mddev->array_size<<1)) {
+ skipped = 1;
+ continue;
+ }
+ memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE);
+ set_bit(R5_Expanded, &sh->dev[j].flags);
+ set_bit(R5_UPTODATE, &sh->dev[j].flags);
+ }
+ if (!skipped) {
+ set_bit(STRIPE_EXPAND_READY, &sh->state);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ }
+ release_stripe(sh);
+ }
+ spin_lock_irq(&conf->device_lock);
+ conf->expand_progress = (sector_nr + i)*(conf->raid_disks-1);
+ spin_unlock_irq(&conf->device_lock);
+ /* Ok, those stripe are ready. We can start scheduling
+ * reads on the source stripes.
+ * The source stripes are determined by mapping the first and last
+ * block on the destination stripes.
+ */
+ raid_disks = conf->previous_raid_disks;
+ data_disks = raid_disks - 1;
+ first_sector =
+ raid5_compute_sector(sector_nr*(conf->raid_disks-1),
+ raid_disks, data_disks,
+ &dd_idx, &pd_idx, conf);
+ last_sector =
+ raid5_compute_sector((sector_nr+conf->chunk_size/512)
+ *(conf->raid_disks-1) -1,
+ raid_disks, data_disks,
+ &dd_idx, &pd_idx, conf);
+ if (last_sector >= (mddev->size<<1))
+ last_sector = (mddev->size<<1)-1;
+ while (first_sector <= last_sector) {
+ pd_idx = stripe_to_pdidx(first_sector, conf, conf->previous_raid_disks);
+ sh = get_active_stripe(conf, first_sector,
+ conf->previous_raid_disks, pd_idx, 0);
+ set_bit(STRIPE_EXPAND_SOURCE, &sh->state);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ release_stripe(sh);
+ first_sector += STRIPE_SECTORS;
+ }
+ return conf->chunk_size>>9;
+ }
/* if there is 1 or more failed drives and we are trying
* to resync, then assert that we are finished, because there is
* nothing we can do.
return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */
}
- x = sector_nr;
- chunk_offset = sector_div(x, sectors_per_chunk);
- stripe = x;
- BUG_ON(x != stripe);
-
- first_sector = raid5_compute_sector((sector_t)stripe*data_disks*sectors_per_chunk
- + chunk_offset, raid_disks, data_disks, &dd_idx, &pd_idx, conf);
- sh = get_active_stripe(conf, sector_nr, pd_idx, 1);
+ pd_idx = stripe_to_pdidx(sector_nr, conf, raid_disks);
+ sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 1);
if (sh == NULL) {
- sh = get_active_stripe(conf, sector_nr, pd_idx, 0);
+ sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 0);
/* make sure we don't swamp the stripe cache if someone else
* is trying to get access
*/
list_del_init(first);
atomic_inc(&sh->count);
- if (atomic_read(&sh->count)!= 1)
- BUG();
+ BUG_ON(atomic_read(&sh->count)!= 1);
spin_unlock_irq(&conf->device_lock);
handled++;
return -EIO;
}
- mddev->private = kzalloc(sizeof (raid5_conf_t)
- + mddev->raid_disks * sizeof(struct disk_info),
- GFP_KERNEL);
+ 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
+ */
+ sector_t here_new, here_old;
+ int old_disks;
+
+ if (mddev->new_level != mddev->level ||
+ mddev->new_layout != mddev->layout ||
+ mddev->new_chunk != mddev->chunk_size) {
+ printk(KERN_ERR "raid5: %s: unsupported reshape required - aborting.\n",
+ mdname(mddev));
+ return -EINVAL;
+ }
+ if (mddev->delta_disks <= 0) {
+ printk(KERN_ERR "raid5: %s: unsupported reshape (reduce disks) required - aborting.\n",
+ mdname(mddev));
+ return -EINVAL;
+ }
+ old_disks = mddev->raid_disks - mddev->delta_disks;
+ /* reshape_position must be on a new-stripe boundary, and one
+ * further up in new geometry must map after here in old geometry.
+ */
+ here_new = mddev->reshape_position;
+ if (sector_div(here_new, (mddev->chunk_size>>9)*(mddev->raid_disks-1))) {
+ printk(KERN_ERR "raid5: reshape_position not on a stripe boundary\n");
+ return -EINVAL;
+ }
+ /* here_new is the stripe we will write to */
+ here_old = mddev->reshape_position;
+ sector_div(here_old, (mddev->chunk_size>>9)*(old_disks-1));
+ /* here_old is the first stripe that we might need to read from */
+ if (here_new >= here_old) {
+ /* Reading from the same stripe as writing to - bad */
+ printk(KERN_ERR "raid5: reshape_position too early for auto-recovery - aborting.\n");
+ return -EINVAL;
+ }
+ printk(KERN_INFO "raid5: reshape will continue\n");
+ /* OK, we should be able to continue; */
+ }
+
+
+ mddev->private = kzalloc(sizeof (raid5_conf_t), GFP_KERNEL);
if ((conf = mddev->private) == NULL)
goto abort;
+ if (mddev->reshape_position == MaxSector) {
+ conf->previous_raid_disks = conf->raid_disks = mddev->raid_disks;
+ } else {
+ conf->raid_disks = mddev->raid_disks;
+ conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks;
+ }
+
+ conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info),
+ GFP_KERNEL);
+ if (!conf->disks)
+ goto abort;
conf->mddev = mddev;
ITERATE_RDEV(mddev,rdev,tmp) {
raid_disk = rdev->raid_disk;
- if (raid_disk >= mddev->raid_disks
+ if (raid_disk >= conf->raid_disks
|| raid_disk < 0)
continue;
disk = conf->disks + raid_disk;
}
}
- conf->raid_disks = mddev->raid_disks;
/*
* 0 for a fully functional array, 1 for a degraded array.
*/
conf->level = mddev->level;
conf->algorithm = mddev->layout;
conf->max_nr_stripes = NR_STRIPES;
+ conf->expand_progress = mddev->reshape_position;
/* device size must be a multiple of chunk size */
mddev->size &= ~(mddev->chunk_size/1024 -1);
print_raid5_conf(conf);
+ if (conf->expand_progress != MaxSector) {
+ printk("...ok start reshape thread\n");
+ conf->expand_lo = conf->expand_progress;
+ atomic_set(&conf->reshape_stripes, 0);
+ clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+ clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
+ set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
+ set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
+ mddev->sync_thread = md_register_thread(md_do_sync, mddev,
+ "%s_reshape");
+ /* FIXME if md_register_thread fails?? */
+ md_wakeup_thread(mddev->sync_thread);
+
+ }
+
/* read-ahead size must cover two whole stripes, which is
* 2 * (n-1) * chunksize where 'n' is the number of raid devices
*/
mddev->queue->unplug_fn = raid5_unplug_device;
mddev->queue->issue_flush_fn = raid5_issue_flush;
+ mddev->array_size = mddev->size * (conf->previous_raid_disks - 1);
- mddev->array_size = mddev->size * (mddev->raid_disks - 1);
return 0;
abort:
if (conf) {
print_raid5_conf(conf);
+ kfree(conf->disks);
kfree(conf->stripe_hashtbl);
kfree(conf);
}
kfree(conf->stripe_hashtbl);
blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
sysfs_remove_group(&mddev->kobj, &raid5_attrs_group);
+ kfree(conf->disks);
kfree(conf);
mddev->private = NULL;
return 0;
printk("sh %llu, count %d.\n",
(unsigned long long)sh->sector, atomic_read(&sh->count));
printk("sh %llu, ", (unsigned long long)sh->sector);
- for (i = 0; i < sh->raid_conf->raid_disks; i++) {
+ for (i = 0; i < sh->disks; i++) {
printk("(cache%d: %p %ld) ",
i, sh->dev[i].page, sh->dev[i].flags);
}
/*
* find the disk ...
*/
- for (disk=0; disk < mddev->raid_disks; disk++)
+ for (disk=0; disk < conf->raid_disks; disk++)
if ((p=conf->disks + disk)->rdev == NULL) {
clear_bit(In_sync, &rdev->flags);
rdev->raid_disk = disk;
return 0;
}
+#ifdef CONFIG_MD_RAID5_RESHAPE
+static int raid5_check_reshape(mddev_t *mddev)
+{
+ raid5_conf_t *conf = mddev_to_conf(mddev);
+ int err;
+
+ if (mddev->delta_disks < 0 ||
+ mddev->new_level != mddev->level)
+ return -EINVAL; /* Cannot shrink array or change level yet */
+ if (mddev->delta_disks == 0)
+ return 0; /* nothing to do */
+
+ /* Can only proceed if there are plenty of stripe_heads.
+ * We need a minimum of one full stripe,, and for sensible progress
+ * it is best to have about 4 times that.
+ * If we require 4 times, then the default 256 4K stripe_heads will
+ * allow for chunk sizes up to 256K, which is probably OK.
+ * If the chunk size is greater, user-space should request more
+ * stripe_heads first.
+ */
+ if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes ||
+ (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) {
+ printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n",
+ (mddev->chunk_size / STRIPE_SIZE)*4);
+ return -ENOSPC;
+ }
+
+ err = resize_stripes(conf, conf->raid_disks + mddev->delta_disks);
+ if (err)
+ return err;
+
+ /* looks like we might be able to manage this */
+ return 0;
+}
+
+static int raid5_start_reshape(mddev_t *mddev)
+{
+ raid5_conf_t *conf = mddev_to_conf(mddev);
+ mdk_rdev_t *rdev;
+ struct list_head *rtmp;
+ int spares = 0;
+ int added_devices = 0;
+
+ if (mddev->degraded ||
+ test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
+ return -EBUSY;
+
+ ITERATE_RDEV(mddev, rdev, rtmp)
+ if (rdev->raid_disk < 0 &&
+ !test_bit(Faulty, &rdev->flags))
+ spares++;
+
+ if (spares < mddev->delta_disks-1)
+ /* Not enough devices even to make a degraded array
+ * of that size
+ */
+ return -EINVAL;
+
+ atomic_set(&conf->reshape_stripes, 0);
+ spin_lock_irq(&conf->device_lock);
+ conf->previous_raid_disks = conf->raid_disks;
+ conf->raid_disks += mddev->delta_disks;
+ conf->expand_progress = 0;
+ conf->expand_lo = 0;
+ spin_unlock_irq(&conf->device_lock);
+
+ /* Add some new drives, as many as will fit.
+ * We know there are enough to make the newly sized array work.
+ */
+ ITERATE_RDEV(mddev, rdev, rtmp)
+ if (rdev->raid_disk < 0 &&
+ !test_bit(Faulty, &rdev->flags)) {
+ if (raid5_add_disk(mddev, rdev)) {
+ char nm[20];
+ set_bit(In_sync, &rdev->flags);
+ conf->working_disks++;
+ added_devices++;
+ sprintf(nm, "rd%d", rdev->raid_disk);
+ sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
+ } else
+ break;
+ }
+
+ mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) - added_devices;
+ mddev->raid_disks = conf->raid_disks;
+ mddev->reshape_position = 0;
+ mddev->sb_dirty = 1;
+
+ clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+ clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
+ set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
+ set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
+ mddev->sync_thread = md_register_thread(md_do_sync, mddev,
+ "%s_reshape");
+ if (!mddev->sync_thread) {
+ mddev->recovery = 0;
+ spin_lock_irq(&conf->device_lock);
+ mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks;
+ conf->expand_progress = MaxSector;
+ spin_unlock_irq(&conf->device_lock);
+ return -EAGAIN;
+ }
+ md_wakeup_thread(mddev->sync_thread);
+ md_new_event(mddev);
+ return 0;
+}
+#endif
+
+static void end_reshape(raid5_conf_t *conf)
+{
+ struct block_device *bdev;
+
+ if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
+ conf->mddev->array_size = conf->mddev->size * (conf->raid_disks-1);
+ set_capacity(conf->mddev->gendisk, conf->mddev->array_size << 1);
+ conf->mddev->changed = 1;
+
+ bdev = bdget_disk(conf->mddev->gendisk, 0);
+ if (bdev) {
+ mutex_lock(&bdev->bd_inode->i_mutex);
+ i_size_write(bdev->bd_inode, conf->mddev->array_size << 10);
+ mutex_unlock(&bdev->bd_inode->i_mutex);
+ bdput(bdev);
+ }
+ spin_lock_irq(&conf->device_lock);
+ conf->expand_progress = MaxSector;
+ spin_unlock_irq(&conf->device_lock);
+ conf->mddev->reshape_position = MaxSector;
+ }
+}
+
static void raid5_quiesce(mddev_t *mddev, int state)
{
raid5_conf_t *conf = mddev_to_conf(mddev);
switch(state) {
+ case 2: /* resume for a suspend */
+ wake_up(&conf->wait_for_overlap);
+ break;
+
case 1: /* stop all writes */
spin_lock_irq(&conf->device_lock);
conf->quiesce = 1;
spin_lock_irq(&conf->device_lock);
conf->quiesce = 0;
wake_up(&conf->wait_for_stripe);
+ wake_up(&conf->wait_for_overlap);
spin_unlock_irq(&conf->device_lock);
break;
}
.spare_active = raid5_spare_active,
.sync_request = sync_request,
.resize = raid5_resize,
+#ifdef CONFIG_MD_RAID5_RESHAPE
+ .check_reshape = raid5_check_reshape,
+ .start_reshape = raid5_start_reshape,
+#endif
.quiesce = raid5_quiesce,
};
projects / linux-flexiantxendom0-3.2.10.git / blobdiff