(Please Cc me on any replies, I'm not subscribed)
Hi,
Attached is a patch (against 2.6.12) for adding online RAID-5 resize
capabilities to Linux' RAID code. It needs to changes to mdadm (I've only
tested with mdadm 1.12.0, though), you can just do
mdadm --add /dev/md1 /dev/hd[eg]1
mdadm --grow /dev/md1 -n 4
and it will restripe /dev/md1; you can still use the volume just fine
during the expand process. (cat /proc/mdstat to get the progress; it will
look like a regular sync, and when the restripe is done the volume will
suddenly get larger and do a regular sync of the new parts.)
The patch is quite rough -- it's my first trip ever into the md code, the
block layer or really kernel code in general, so expect subtle race
conditions and problems here and there. :-) That being said, it seems to be
quite stable on my (SMP) test system now -- I would really take backups
before testing it, though! You have been warned :-)
Things still to do, off the top of my head:
- It's RAID-5 only; I don't really use RAID-0, and RAID-6 would probably be
more complex.
- It supports only growing, not shrinking. (Not sure if I really care about
fixing this one.)
- It leaks memory; it doesn't properly free up the old stripes etc. at the
end of the resize. (This also makes it impossible to do a grow and then
another grow without stopping and starting the volumes.)
- There is absolutely no crash recovery -- this shouldn't be so hard to do
(just update the superblock every time, with some progress meter, and
restart from that spot in case of a crash), but I have no knowledge of the
on-disk superblock format at all, so some help would be appreciated here.
Also, I'm not really sure what happens if it encounters a bad block during
the restripe.
- It's quite slow; on my test system with old IDE disks, it achieves about
1MB/sec. One could probably make a speed/memory tradeoff here, and move
more chunks at a time instead of just one by one; I'm a bit concerned
about the implications of the kernel allocating something like 64MB in one
go, though :-)
Comments, patches, fixes etc. would be greatly appreciated. (Again, remember
to Cc me, I'm not on the list.)
/* Steinar */
--
Homepage: http://www.sesse.net/
diff -ur linux-2.6-2.6.12/drivers/md/raid5.c ../linux-2.6-2.6.12/drivers/md/raid5.c
--- linux-2.6-2.6.12/drivers/md/raid5.c 2005-06-17 21:48:29.000000000 +0200
+++ linux-2.6-2.6.12.patch/drivers/md/raid5.c 2005-09-20 00:13:55.000000000 +0200
@@ -68,19 +68,40 @@
#endif
static void print_raid5_conf (raid5_conf_t *conf);
+#if RAID5_DEBUG
+static void print_sh (struct stripe_head *sh);
+#endif
+static int sync_request (mddev_t *mddev, sector_t sector_nr, int go_faster);
+static void raid5_finish_expand (raid5_conf_t *conf);
+static sector_t raid5_compute_sector(sector_t r_sector, unsigned int raid_disks,
+ unsigned int data_disks, unsigned int * dd_idx,
+ unsigned int * pd_idx, raid5_conf_t *conf);
static inline void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh)
{
+ PRINTK("__release_stripe, conf=%p\n", conf);
+ BUG_ON(atomic_read(&sh->count) == 0);
if (atomic_dec_and_test(&sh->count)) {
if (!list_empty(&sh->lru))
BUG();
- if (atomic_read(&conf->active_stripes)==0)
- BUG();
+ if (conf->expand_in_progress && sh->disks == conf->raid_disks) {
+ if (atomic_read(&conf->active_stripes_expand)==0)
+ BUG();
+ } else {
+ if (atomic_read(&conf->active_stripes)==0)
+ BUG();
+ }
if (test_bit(STRIPE_HANDLE, &sh->state)) {
- if (test_bit(STRIPE_DELAYED, &sh->state))
+ if (test_bit(STRIPE_DELAY_EXPAND, &sh->state)) {
+ list_add_tail(&sh->lru, &conf->wait_for_expand_list);
+ printk("delaying stripe with sector %llu (expprog=%llu, active=%d)\n", sh->sector,
+ conf->expand_progress, atomic_read(&conf->active_stripes_expand));
+ } else if (test_bit(STRIPE_DELAYED, &sh->state)) {
+// printk("real-delay\n");
list_add_tail(&sh->lru, &conf->delayed_list);
- else
+ } else {
list_add_tail(&sh->lru, &conf->handle_list);
+ }
md_wakeup_thread(conf->mddev->thread);
} else {
if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
@@ -88,11 +109,34 @@
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) < (NR_STRIPES*3/4))
- wake_up(&conf->wait_for_stripe);
+ if (conf->expand_in_progress && sh->disks == conf->raid_disks) {
+ list_add_tail(&sh->lru, &conf->inactive_list_expand);
+ atomic_dec(&conf->active_stripes_expand);
+ } else {
+ list_add_tail(&sh->lru, &conf->inactive_list);
+ if (conf->expand_in_progress == 2) {
+ // we are in the process of finishing up an expand, see
+ // if we have no active stripes left
+ if (atomic_dec_and_test(&conf->active_stripes)) {
+ printk("Finishing up expand\n");
+ raid5_finish_expand(conf);
+ printk("Expand done.\n");
+ }
+ } else {
+ atomic_dec(&conf->active_stripes);
+ }
+ }
+ if (conf->expand_in_progress && sh->disks == conf->raid_disks) {
+ if (!conf->inactive_blocked_expand ||
+ atomic_read(&conf->active_stripes_expand) < (NR_STRIPES*3/4)) {
+ wake_up(&conf->wait_for_stripe_expand);
+ }
+ } else {
+ if (!conf->inactive_blocked ||
+ atomic_read(&conf->active_stripes) < (NR_STRIPES*3/4)) {
+ wake_up(&conf->wait_for_stripe);
+ }
+ }
}
}
}
@@ -133,20 +177,44 @@
/* find an idle stripe, make sure it is unhashed, and return it. */
-static struct stripe_head *get_free_stripe(raid5_conf_t *conf)
+static struct stripe_head *get_free_stripe(raid5_conf_t *conf, int expand)
{
struct stripe_head *sh = NULL;
struct list_head *first;
CHECK_DEVLOCK();
- if (list_empty(&conf->inactive_list))
- goto out;
- first = conf->inactive_list.next;
- sh = list_entry(first, struct stripe_head, lru);
- list_del_init(first);
- remove_hash(sh);
- atomic_inc(&conf->active_stripes);
+
+ if (expand) {
+ if (list_empty(&conf->inactive_list_expand))
+ goto out;
+ first = conf->inactive_list_expand.next;
+ sh = list_entry(first, struct stripe_head, lru);
+ list_del_init(first);
+ remove_hash(sh);
+ atomic_inc(&conf->active_stripes_expand);
+ } else {
+ if (list_empty(&conf->inactive_list))
+ goto out;
+ first = conf->inactive_list.next;
+ sh = list_entry(first, struct stripe_head, lru);
+ list_del_init(first);
+ remove_hash(sh);
+ atomic_inc(&conf->active_stripes);
+ }
out:
+
+ if (sh) {
+ if (conf->expand_in_progress) {
+ if (expand)
+ BUG_ON(sh->disks != conf->raid_disks);
+ else
+ BUG_ON(sh->disks != conf->previous_raid_disks);
+ } else {
+ BUG_ON(expand);
+ BUG_ON(sh->disks != conf->raid_disks);
+ }
+ }
+
return sh;
}
@@ -184,7 +252,7 @@
static inline void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx)
{
raid5_conf_t *conf = sh->raid_conf;
- int disks = conf->raid_disks, i;
+ int disks = sh->disks, i;
if (atomic_read(&sh->count) != 0)
BUG();
@@ -245,21 +313,59 @@
do {
sh = __find_stripe(conf, sector);
+
+ // make sure this is of the right size; if not, remove it from the hash
+ if (sh) {
+ int correct_disks = conf->raid_disks;
+ if (conf->expand_in_progress && sector >= conf->expand_progress) {
+ correct_disks = conf->previous_raid_disks;
+ }
+
+ if (sh->disks != correct_disks) {
+ BUG_ON(atomic_read(&sh->count) != 0);
+
+ remove_hash(sh);
+ sh = NULL;
+ }
+ }
+
if (!sh) {
- if (!conf->inactive_blocked)
- sh = get_free_stripe(conf);
+ if (conf->expand_in_progress && sector * (conf->raid_disks - 1) < conf->expand_progress) {
+ if (!conf->inactive_blocked_expand) {
+ sh = get_free_stripe(conf, 1);
+ }
+ } else {
+ if (!conf->inactive_blocked) {
+ sh = get_free_stripe(conf, 0);
+ }
+ }
if (noblock && sh == NULL)
break;
if (!sh) {
- conf->inactive_blocked = 1;
- wait_event_lock_irq(conf->wait_for_stripe,
- !list_empty(&conf->inactive_list) &&
- (atomic_read(&conf->active_stripes) < (NR_STRIPES *3/4)
- || !conf->inactive_blocked),
- conf->device_lock,
- unplug_slaves(conf->mddev);
- );
- conf->inactive_blocked = 0;
+ if (conf->expand_in_progress && sector * (conf->raid_disks - 1) < conf->expand_progress) {
+// printk("WAITING FOR AN EXPAND STRIPE\n");
+ conf->inactive_blocked_expand = 1;
+ wait_event_lock_irq(conf->wait_for_stripe_expand,
+ !list_empty(&conf->inactive_list_expand) &&
+ (atomic_read(&conf->active_stripes_expand) < (NR_STRIPES *3/4)
+ || !conf->inactive_blocked_expand),
+ conf->device_lock,
+ unplug_slaves(conf->mddev);
+ );
+ conf->inactive_blocked_expand = 0;
+ } else {
+// printk("WAITING FOR A NON-EXPAND STRIPE, sector=%llu\n", sector);
+ conf->inactive_blocked = 1;
+ wait_event_lock_irq(conf->wait_for_stripe,
+ !list_empty(&conf->inactive_list) &&
+ (atomic_read(&conf->active_stripes) < (NR_STRIPES *3/4)
+ || !conf->inactive_blocked),
+ conf->device_lock,
+ unplug_slaves(conf->mddev);
+ );
+ conf->inactive_blocked = 0;
+ }
+// printk("INACTIVITY DONE\n");
} else
init_stripe(sh, sector, pd_idx);
} else {
@@ -267,8 +373,13 @@
if (!list_empty(&sh->lru))
BUG();
} else {
- if (!test_bit(STRIPE_HANDLE, &sh->state))
- atomic_inc(&conf->active_stripes);
+ if (!test_bit(STRIPE_HANDLE, &sh->state)) {
+ if (conf->expand_in_progress && sector < conf->expand_progress) {
+ atomic_inc(&conf->active_stripes_expand);
+ } else {
+ atomic_inc(&conf->active_stripes);
+ }
+ }
if (list_empty(&sh->lru))
BUG();
list_del_init(&sh->lru);
@@ -283,26 +394,34 @@
return sh;
}
-static int grow_stripes(raid5_conf_t *conf, int num)
+static int grow_stripes(raid5_conf_t *conf, int num, int expand)
{
struct stripe_head *sh;
kmem_cache_t *sc;
int devs = conf->raid_disks;
- sprintf(conf->cache_name, "raid5/%s", mdname(conf->mddev));
+ if (expand)
+ sprintf(conf->cache_name, "raid5e/%s", mdname(conf->mddev));
+ else
+ sprintf(conf->cache_name, "raid5/%s", mdname(conf->mddev));
sc = kmem_cache_create(conf->cache_name,
sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
0, 0, NULL, NULL);
if (!sc)
return 1;
- conf->slab_cache = sc;
+ if (expand)
+ conf->slab_cache_expand = sc;
+ else
+ conf->slab_cache = sc;
while (num--) {
sh = kmem_cache_alloc(sc, GFP_KERNEL);
if (!sh)
return 1;
+ printk("alloc stripe: %p\n", sh);
memset(sh, 0, sizeof(*sh) + (devs-1)*sizeof(struct r5dev));
sh->raid_conf = conf;
+ sh->disks = conf->raid_disks;
spin_lock_init(&sh->lock);
if (grow_buffers(sh, conf->raid_disks)) {
@@ -312,10 +431,15 @@
}
/* we just created an active stripe so... */
atomic_set(&sh->count, 1);
- atomic_inc(&conf->active_stripes);
+ if (expand) {
+ atomic_inc(&conf->active_stripes_expand);
+ } else {
+ atomic_inc(&conf->active_stripes);
+ }
INIT_LIST_HEAD(&sh->lru);
release_stripe(sh);
}
+ printk("done growing\n");
return 0;
}
@@ -325,7 +449,7 @@
while (1) {
spin_lock_irq(&conf->device_lock);
- sh = get_free_stripe(conf);
+ sh = get_free_stripe(conf, 0);
spin_unlock_irq(&conf->device_lock);
if (!sh)
break;
@@ -344,7 +468,7 @@
{
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)
@@ -393,6 +517,8 @@
set_bit(R5_UPTODATE, &sh->dev[i].flags);
#endif
} else {
+ printk("received non-up-to-date information for disk %u, sector %llu!\n",
+ i, sh->sector);
md_error(conf->mddev, conf->disks[i].rdev);
clear_bit(R5_UPTODATE, &sh->dev[i].flags);
}
@@ -411,12 +537,93 @@
return 0;
}
+
+static void raid5_finish_expand (raid5_conf_t *conf)
+{
+ int i;
+ struct disk_info *tmp;
+// shrink_stripes(conf);
+
+ conf->expand_in_progress = 0;
+ conf->active_stripes = conf->active_stripes_expand;
+ conf->inactive_list = conf->inactive_list_expand;
+ conf->wait_for_stripe = conf->wait_for_stripe_expand;
+ conf->slab_cache = conf->slab_cache_expand;
+ conf->inactive_blocked = conf->inactive_blocked_expand;
+
+ // fix up linked list
+ conf->inactive_list.next->prev = &conf->inactive_list;
+ {
+ struct list_head *first = &conf->inactive_list;
+ while (1) {
+ if (first->next == &conf->inactive_list_expand) {
+ first->next = &conf->inactive_list;
+ break;
+ }
+
+ first = first->next;
+ }
+ }
+
+ conf->wait_for_stripe.task_list.next->prev = &conf->wait_for_stripe.task_list;
+ {
+ struct list_head *first = &conf->wait_for_stripe.task_list;
+ while (1) {
+ if (first->next == &conf->wait_for_stripe_expand.task_list) {
+ first->next = &conf->wait_for_stripe.task_list;
+ break;
+ }
+
+ first = first->next;
+ }
+ }
+
+ for (i = conf->previous_raid_disks; i < conf->raid_disks; i++) {
+ tmp = conf->disks + i;
+ if (tmp->rdev
+ && !tmp->rdev->faulty
+ && !tmp->rdev->in_sync) {
+ conf->mddev->degraded--;
+ conf->failed_disks--;
+ conf->working_disks++;
+ tmp->rdev->in_sync = 1;
+ }
+ }
+
+ // hey, mr. md code: we have more space now!
+ {
+ struct block_device *bdev;
+ sector_t sync_sector;
+ unsigned dummy1, dummy2;
+
+ conf->mddev->array_size = conf->mddev->size * (conf->mddev->raid_disks-1);
+ set_capacity(conf->mddev->gendisk, conf->mddev->array_size << 1);
+ conf->mddev->changed = 1;
+
+ sync_sector = raid5_compute_sector(conf->expand_progress, conf->raid_disks,
+ conf->raid_disks - 1, &dummy1, &dummy2, conf);
+
+ conf->mddev->recovery_cp = sync_sector << 1; // FIXME: hum, hum
+ set_bit(MD_RECOVERY_NEEDED, &conf->mddev->recovery);
+
+ bdev = bdget_disk(conf->mddev->gendisk, 0);
+ if (bdev) {
+ down(&bdev->bd_inode->i_sem);
+ i_size_write(bdev->bd_inode, conf->mddev->array_size << 10);
+ up(&bdev->bd_inode->i_sem);
+ bdput(bdev);
+ }
+ }
+
+ /* FIXME: free old stuff here! (what are we missing?) */
+}
+
static int raid5_end_write_request (struct bio *bi, unsigned int bytes_done,
int error)
{
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);
@@ -436,8 +643,11 @@
}
spin_lock_irqsave(&conf->device_lock, flags);
- if (!uptodate)
+ if (!uptodate) {
+ printk("end_write_request ends with error, for disk %u sector %llu\n",
+ i, sh->sector);
md_error(conf->mddev, conf->disks[i].rdev);
+ }
rdev_dec_pending(conf->disks[i].rdev, conf->mddev);
@@ -512,12 +722,14 @@
int sectors_per_chunk = conf->chunk_size >> 9;
/* First compute the information on this sector */
+ PRINTK("r_sector_inp=%llu\n", r_sector);
/*
* Compute the chunk number and the sector offset inside the chunk
*/
chunk_offset = sector_div(r_sector, sectors_per_chunk);
chunk_number = r_sector;
+ PRINTK("r_sector=%llu, chunk_number=%lu\n", r_sector, chunk_number);
BUG_ON(r_sector != chunk_number);
/*
@@ -556,7 +768,7 @@
break;
default:
printk("raid5: unsupported algorithm %d\n",
- conf->algorithm);
+ conf->algorithm);
}
/*
@@ -570,7 +782,7 @@
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;
@@ -582,7 +794,7 @@
stripe = new_sector;
BUG_ON(new_sector != stripe);
-
+
switch (conf->algorithm) {
case ALGORITHM_LEFT_ASYMMETRIC:
case ALGORITHM_RIGHT_ASYMMETRIC:
@@ -597,7 +809,7 @@
break;
default:
printk("raid5: unsupported algorithm %d\n",
- conf->algorithm);
+ conf->algorithm);
}
chunk_number = stripe * data_disks + i;
@@ -605,7 +817,8 @@
check = raid5_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf);
if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) {
- printk("compute_blocknr: map not correct\n");
+ printk("compute_blocknr: map not correct (%llu,%u,%u vs. %llu,%u,%u) disks=%u offset=%u virtual_dd=%u\n",
+ check, dummy1, dummy2, sh->sector, dd_idx, sh->pd_idx, sh->disks, chunk_offset, i);
return 0;
}
return r_sector;
@@ -620,8 +833,8 @@
* All iovecs in the bio must be considered.
*/
static void copy_data(int frombio, struct bio *bio,
- struct page *page,
- sector_t sector)
+ struct page *page,
+ sector_t sector)
{
char *pa = page_address(page);
struct bio_vec *bvl;
@@ -646,7 +859,7 @@
if (len > 0 && page_offset + len > STRIPE_SIZE)
clen = STRIPE_SIZE - page_offset;
else clen = len;
-
+
if (clen > 0) {
char *ba = __bio_kmap_atomic(bio, i, KM_USER0);
if (frombio)
@@ -662,21 +875,21 @@
}
#define check_xor() do { \
- if (count == MAX_XOR_BLOCKS) { \
- xor_block(count, STRIPE_SIZE, ptr); \
- count = 1; \
- } \
- } while(0)
+ if (count == MAX_XOR_BLOCKS) { \
+ xor_block(count, STRIPE_SIZE, ptr); \
+ count = 1; \
+ } \
+} while(0)
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;
+ // raid5_conf_t *conf = sh->raid_conf;
+ int i, count, disks = sh->disks;
void *ptr[MAX_XOR_BLOCKS], *p;
PRINTK("compute_block, stripe %llu, idx %d\n",
- (unsigned long long)sh->sector, dd_idx);
+ (unsigned long long)sh->sector, dd_idx);
ptr[0] = page_address(sh->dev[dd_idx].page);
memset(ptr[0], 0, STRIPE_SIZE);
@@ -689,8 +902,8 @@
ptr[count++] = p;
else
printk("compute_block() %d, stripe %llu, %d"
- " not present\n", dd_idx,
- (unsigned long long)sh->sector, i);
+ " not present\n", dd_idx,
+ (unsigned long long)sh->sector, i);
check_xor();
}
@@ -702,59 +915,59 @@
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;
PRINTK("compute_parity, stripe %llu, method %d\n",
- (unsigned long long)sh->sector, method);
+ (unsigned long long)sh->sector, method);
count = 1;
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();
- for (i=disks ; i-- ;) {
- if (i==pd_idx)
- continue;
- if (sh->dev[i].towrite &&
- test_bit(R5_UPTODATE, &sh->dev[i].flags)) {
- ptr[count++] = page_address(sh->dev[i].page);
- chosen = sh->dev[i].towrite;
- sh->dev[i].towrite = NULL;
-
- if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
- wake_up(&conf->wait_for_overlap);
-
- if (sh->dev[i].written) BUG();
- sh->dev[i].written = chosen;
- check_xor();
+ case READ_MODIFY_WRITE:
+ if (!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags))
+ BUG();
+ for (i=disks ; i-- ;) {
+ if (i==pd_idx)
+ continue;
+ if (sh->dev[i].towrite &&
+ test_bit(R5_UPTODATE, &sh->dev[i].flags)) {
+ ptr[count++] = page_address(sh->dev[i].page);
+ chosen = sh->dev[i].towrite;
+ sh->dev[i].towrite = NULL;
+
+ if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
+ wake_up(&conf->wait_for_overlap);
+
+ if (sh->dev[i].written) BUG();
+ sh->dev[i].written = chosen;
+ check_xor();
+ }
}
- }
- break;
- case RECONSTRUCT_WRITE:
- memset(ptr[0], 0, STRIPE_SIZE);
- for (i= disks; i-- ;)
- if (i!=pd_idx && sh->dev[i].towrite) {
- chosen = sh->dev[i].towrite;
- sh->dev[i].towrite = NULL;
+ break;
+ case RECONSTRUCT_WRITE:
+ memset(ptr[0], 0, STRIPE_SIZE);
+ for (i= disks; i-- ;)
+ if (i!=pd_idx && sh->dev[i].towrite) {
+ chosen = sh->dev[i].towrite;
+ sh->dev[i].towrite = NULL;
- if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
- wake_up(&conf->wait_for_overlap);
+ if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
+ wake_up(&conf->wait_for_overlap);
- if (sh->dev[i].written) BUG();
- sh->dev[i].written = chosen;
- }
- break;
- case CHECK_PARITY:
- break;
+ if (sh->dev[i].written) BUG();
+ sh->dev[i].written = chosen;
+ }
+ break;
+ case CHECK_PARITY:
+ break;
}
if (count>1) {
xor_block(count, STRIPE_SIZE, ptr);
count = 1;
}
-
+
for (i = disks; i--;)
if (sh->dev[i].written) {
sector_t sector = sh->dev[i].sector;
@@ -769,24 +982,24 @@
}
switch(method) {
- case RECONSTRUCT_WRITE:
- case CHECK_PARITY:
- for (i=disks; i--;)
- if (i != pd_idx) {
- ptr[count++] = page_address(sh->dev[i].page);
- check_xor();
- }
- break;
- case READ_MODIFY_WRITE:
- for (i = disks; i--;)
- if (sh->dev[i].written) {
- ptr[count++] = page_address(sh->dev[i].page);
- check_xor();
- }
+ case RECONSTRUCT_WRITE:
+ case CHECK_PARITY:
+ for (i=disks; i--;)
+ if (i != pd_idx) {
+ ptr[count++] = page_address(sh->dev[i].page);
+ check_xor();
+ }
+ break;
+ case READ_MODIFY_WRITE:
+ for (i = disks; i--;)
+ if (sh->dev[i].written) {
+ ptr[count++] = page_address(sh->dev[i].page);
+ check_xor();
+ }
}
if (count != 1)
xor_block(count, STRIPE_SIZE, ptr);
-
+
if (method != CHECK_PARITY) {
set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
@@ -805,16 +1018,18 @@
raid5_conf_t *conf = sh->raid_conf;
PRINTK("adding bh b#%llu to stripe s#%llu\n",
- (unsigned long long)bi->bi_sector,
- (unsigned long long)sh->sector);
+ (unsigned long long)bi->bi_sector,
+ (unsigned long long)sh->sector);
spin_lock(&sh->lock);
spin_lock_irq(&conf->device_lock);
+ PRINTK("lock, DISKS: %u\n", sh->disks);
if (forwrite)
bip = &sh->dev[dd_idx].towrite;
else
bip = &sh->dev[dd_idx].toread;
+ PRINTK("pip, disk=%u, bip=%p, num_disks=%u\n", dd_idx, bip, sh->disks);
while (*bip && (*bip)->bi_sector < bi->bi_sector) {
if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector)
goto overlap;
@@ -833,16 +1048,16 @@
spin_unlock(&sh->lock);
PRINTK("added bi b#%llu to stripe s#%llu, disk %d.\n",
- (unsigned long long)bi->bi_sector,
- (unsigned long long)sh->sector, dd_idx);
+ (unsigned long long)bi->bi_sector,
+ (unsigned long long)sh->sector, dd_idx);
if (forwrite) {
/* check if page is covered */
sector_t sector = sh->dev[dd_idx].sector;
for (bi=sh->dev[dd_idx].towrite;
- sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
- bi && bi->bi_sector <= sector;
- bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
+ sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
+ bi && bi->bi_sector <= sector;
+ bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
if (bi->bi_sector + (bi->bi_size>>9) >= sector)
sector = bi->bi_sector + (bi->bi_size>>9);
}
@@ -851,7 +1066,9 @@
}
return 1;
- overlap:
+overlap:
+ printk("overlap\n");
+
set_bit(R5_Overlap, &sh->dev[dd_idx].flags);
spin_unlock_irq(&conf->device_lock);
spin_unlock(&sh->lock);
@@ -876,11 +1093,11 @@
* get BH_Lock set before the stripe lock is released.
*
*/
-
+
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;
@@ -891,12 +1108,13 @@
struct r5dev *dev;
PRINTK("handling stripe %llu, cnt=%d, pd_idx=%d\n",
- (unsigned long long)sh->sector, atomic_read(&sh->count),
- sh->pd_idx);
+ (unsigned long long)sh->sector, atomic_read(&sh->count),
+ sh->pd_idx);
spin_lock(&sh->lock);
clear_bit(STRIPE_HANDLE, &sh->state);
clear_bit(STRIPE_DELAYED, &sh->state);
+ clear_bit(STRIPE_DELAY_EXPAND, &sh->state);
syncing = test_bit(STRIPE_SYNCING, &sh->state);
/* Now to look around and see what can be done */
@@ -908,7 +1126,7 @@
clear_bit(R5_Syncio, &dev->flags);
PRINTK("check %d: state 0x%lx read %p write %p written %p\n",
- i, dev->flags, dev->toread, dev->towrite, dev->written);
+ i, dev->flags, dev->toread, dev->towrite, dev->written);
/* maybe we can reply to a read */
if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) {
struct bio *rbi, *rbi2;
@@ -936,7 +1154,7 @@
if (test_bit(R5_LOCKED, &dev->flags)) locked++;
if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++;
-
+
if (dev->toread) to_read++;
if (dev->towrite) {
to_write++;
@@ -945,19 +1163,21 @@
}
if (dev->written) written++;
rdev = conf->disks[i].rdev; /* FIXME, should I be looking rdev */
- if (!rdev || !rdev->in_sync) {
+ if (!conf->expand_in_progress && (!rdev || !rdev->in_sync)) {
failed++;
failed_num = i;
+ printk("failing disk %u (%p)!\n", i, rdev);
} else
set_bit(R5_Insync, &dev->flags);
}
- PRINTK("locked=%d uptodate=%d to_read=%d"
- " to_write=%d failed=%d failed_num=%d\n",
- locked, uptodate, to_read, to_write, failed, failed_num);
/* check if the array has lost two devices and, if so, some requests might
* need to be failed
*/
if (failed > 1 && to_read+to_write+written) {
+ printk("Need to fail requests!\n");
+ printk("locked=%d uptodate=%d to_read=%d"
+ " to_write=%d failed=%d failed_num=%d disks=%d\n",
+ locked, uptodate, to_read, to_write, failed, failed_num, disks);
spin_lock_irq(&conf->device_lock);
for (i=disks; i--; ) {
/* fail all writes first */
@@ -1012,7 +1232,7 @@
}
spin_unlock_irq(&conf->device_lock);
}
- if (failed > 1 && syncing) {
+ if (failed > 1 && syncing && !conf->expand_in_progress) {
md_done_sync(conf->mddev, STRIPE_SECTORS,0);
clear_bit(STRIPE_SYNCING, &sh->state);
syncing = 0;
@@ -1023,37 +1243,37 @@
*/
dev = &sh->dev[sh->pd_idx];
if ( written &&
- ( (test_bit(R5_Insync, &dev->flags) && !test_bit(R5_LOCKED, &dev->flags) &&
- test_bit(R5_UPTODATE, &dev->flags))
- || (failed == 1 && failed_num == sh->pd_idx))
- ) {
- /* any written block on an uptodate or failed drive can be returned.
- * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
- * never LOCKED, so we don't need to test 'failed' directly.
- */
- for (i=disks; i--; )
- if (sh->dev[i].written) {
- dev = &sh->dev[i];
- if (!test_bit(R5_LOCKED, &dev->flags) &&
- test_bit(R5_UPTODATE, &dev->flags) ) {
- /* We can return any write requests */
- struct bio *wbi, *wbi2;
- PRINTK("Return write for disc %d\n", i);
- spin_lock_irq(&conf->device_lock);
- wbi = dev->written;
- dev->written = NULL;
- while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) {
- wbi2 = r5_next_bio(wbi, dev->sector);
- if (--wbi->bi_phys_segments == 0) {
- md_write_end(conf->mddev);
- wbi->bi_next = return_bi;
- return_bi = wbi;
- }
- wbi = wbi2;
- }
- spin_unlock_irq(&conf->device_lock);
- }
- }
+ ( (test_bit(R5_Insync, &dev->flags) && !test_bit(R5_LOCKED, &dev->flags) &&
+ test_bit(R5_UPTODATE, &dev->flags))
+ || (failed == 1 && failed_num == sh->pd_idx))
+ ) {
+ /* any written block on an uptodate or failed drive can be returned.
+ * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
+ * never LOCKED, so we don't need to test 'failed' directly.
+ */
+ for (i=disks; i--; )
+ if (sh->dev[i].written) {
+ dev = &sh->dev[i];
+ if (!test_bit(R5_LOCKED, &dev->flags) &&
+ test_bit(R5_UPTODATE, &dev->flags) ) {
+ /* We can return any write requests */
+ struct bio *wbi, *wbi2;
+ PRINTK("Return write for disc %d\n", i);
+ spin_lock_irq(&conf->device_lock);
+ wbi = dev->written;
+ dev->written = NULL;
+ while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) {
+ wbi2 = r5_next_bio(wbi, dev->sector);
+ if (--wbi->bi_phys_segments == 0) {
+ md_write_end(conf->mddev);
+ wbi->bi_next = return_bi;
+ return_bi = wbi;
+ }
+ wbi = wbi2;
+ }
+ spin_unlock_irq(&conf->device_lock);
+ }
+ }
}
/* Now we might consider reading some blocks, either to check/generate
@@ -1064,13 +1284,13 @@
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 ||
- (failed && (sh->dev[failed_num].toread ||
- (sh->dev[failed_num].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num].flags))))
- )
- ) {
+ (dev->toread ||
+ (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
+ syncing ||
+ (failed && (sh->dev[failed_num].toread ||
+ (sh->dev[failed_num].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num].flags))))
+ )
+ ) {
/* we would like to get this block, possibly
* by computing it, but we might not be able to
*/
@@ -1085,23 +1305,303 @@
/* if I am just reading this block and we don't have
a failed drive, or any pending writes then sidestep the cache */
if (sh->bh_read[i] && !sh->bh_read[i]->b_reqnext &&
- ! syncing && !failed && !to_write) {
+ ! syncing && !failed && !to_write) {
sh->bh_cache[i]->b_page = sh->bh_read[i]->b_page;
sh->bh_cache[i]->b_data = sh->bh_read[i]->b_data;
}
#endif
locked++;
PRINTK("Reading block %d (sync=%d)\n",
- i, syncing);
- if (syncing)
+ i, syncing);
+ if (syncing && !conf->expand_in_progress)
md_sync_acct(conf->disks[i].rdev->bdev,
- STRIPE_SECTORS);
+ STRIPE_SECTORS);
}
}
}
set_bit(STRIPE_HANDLE, &sh->state);
}
+ // see if we have the data we need to expand by another block
+ if (conf->expand_in_progress && sh->disks == conf->previous_raid_disks) {
+ int uptodate = 0, delay_to_future=0, d = 0, count = 0, needed_uptodate = 0;
+ for (i=0; i<disks; ++i) {
+ sector_t start_sector, dest_sector;
+ unsigned int dd_idx, pd_idx;
+
+ if (i == sh->pd_idx)
+ continue;
+
+ start_sector = sh->sector * (conf->previous_raid_disks - 1) + d * (conf->chunk_size >> 9);
+ ++d;
+
+ // see what sector this block would land in the new layout
+ dest_sector = raid5_compute_sector(start_sector, conf->raid_disks,
+ conf->raid_disks - 1, &dd_idx, &pd_idx, conf);
+ if (dd_idx > pd_idx)
+ --dd_idx;
+
+/* printk("start_sector = %llu (base=%llu, i=%u, d=%u) || dest_stripe = %llu\n", start_sector, sh->sector,
+ i, d, dest_stripe); */
+
+ if (dest_sector * (conf->raid_disks - 1) >= conf->expand_progress &&
+ dest_sector * (conf->raid_disks - 1) < conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1)) {
+/* printk("UPDATING CHUNK %u FROM DISK %u (sec=%llu, dest_sector=%llu, uptodate=%u)\n",
+ dd_idx, i, start_sector, dest_sector, test_bit(R5_UPTODATE, &sh->dev[i].flags)); */
+ unsigned int buf_sector;
+ sector_t base = conf->expand_progress;
+ sector_div(base, conf->raid_disks - 1);
+
+ buf_sector = dd_idx * (conf->chunk_size / STRIPE_SIZE) + (dest_sector - base) / STRIPE_SECTORS;
+
+ if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) {
+ conf->expand_buffer[buf_sector].up_to_date = 1;
+// printk("memcpy device %u/%u: %p <- %p\n", i, sh->disks,
+// page_address(conf->expand_buffer[buf_sector].page), page_address(sh->dev[i].page));
+ memcpy(page_address(conf->expand_buffer[buf_sector].page), page_address(sh->dev[i].page), STRIPE_SIZE);
+// printk("memcpy done\n");
+ count = 1;
+ PRINTK("Updating %u\n", buf_sector);
+ } else {
+ conf->expand_buffer[buf_sector].up_to_date = 0;
+ }
+ } else if (dest_sector * (conf->raid_disks - 1) >= conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1) &&
+ dest_sector * (conf->raid_disks - 1) < conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1) * 2 &&
+ syncing) {
+ delay_to_future = 1;
+ }
+ }
+
+ for (i=0; i < (conf->raid_disks - 1) * (conf->chunk_size / STRIPE_SIZE); ++i) {
+ uptodate += conf->expand_buffer[i].up_to_date;
+ }
+ if (count)
+ PRINTK("%u/%lu is up to date\n", uptodate, (conf->raid_disks - 1) * (conf->chunk_size / STRIPE_SIZE));
+
+ /*
+ * Figure out how many stripes we need for this chunk to be complete.
+ * In almost all cases, this will be a full destination stripe, but our
+ * original volume might not be big enough for that at the very end --
+ * so use the rest of the volume then.
+ */
+ needed_uptodate = (conf->raid_disks - 1) * (conf->chunk_size / STRIPE_SIZE);
+ if (((conf->mddev->size << 1) - conf->expand_progress) / STRIPE_SECTORS < needed_uptodate) {
+ needed_uptodate = ((conf->mddev->size << 1) - conf->expand_progress) / STRIPE_SECTORS;
+// printk("reading partial block at the end: %u\n", needed_uptodate);
+ }
+ if (needed_uptodate > 0 && uptodate == needed_uptodate) {
+ // we can do an expand!
+ struct stripe_head *newsh[256]; // FIXME: dynamic allocation somewhere instead?
+ sector_t dest_sector, advance;
+ unsigned i;
+ unsigned int dummy1, dummy2, pd_idx;
+
+ if ((conf->mddev->size << 1) - conf->expand_progress > (conf->chunk_size >> 9) * (conf->raid_disks - 1)) {
+ advance = (conf->chunk_size * (conf->raid_disks - 1)) >> 9;
+ } else {
+ advance = (conf->mddev->size << 1) - conf->expand_progress;
+ }
+
+// sector_div(new_sector, (conf->raid_disks - 1));
+// printk("EXPANDING ONTO SECTOR %llu\n", conf->expand_progress);
+// printk("EXPAND => %llu/%llu\n", conf->expand_progress, conf->mddev->size << 1);
+
+ // find the parity disk and starting sector
+ dest_sector = raid5_compute_sector(conf->expand_progress, conf->raid_disks,
+ conf->raid_disks - 1, &dummy1, &pd_idx, conf);
+ printk("Expanding onto %llu\n", dest_sector);
+
+ spin_lock_irq(&conf->device_lock);
+
+ /*
+ * Check that we won't try to expand over an area where there's
+ * still active stripes; if we do, we'll risk inconsistency since we
+ * suddenly have two different sets of stripes referring to the
+ * same logical sector.
+ */
+ {
+ struct stripe_head *ash;
+ int activity = 0, i;
+ sector_t first_touched_sector, last_touched_sector;
+
+ first_touched_sector = raid5_compute_sector(conf->expand_progress,
+ conf->previous_raid_disks, conf->previous_raid_disks - 1, &dummy1, &dummy2, conf);
+ last_touched_sector = raid5_compute_sector(conf->expand_progress + ((conf->chunk_size * (conf->previous_raid_disks - 1)) >> 9) - 1,
+ conf->previous_raid_disks, conf->previous_raid_disks - 1, &dummy1, &dummy2, conf);
+
+ for (i = 0; i < NR_HASH; i++) {
+ ash = conf->stripe_hashtbl[i];
+ for (; ash; ash = ash->hash_next) {
+ if (sh == ash && atomic_read(&ash->count) == 1 && !to_write)
+ continue; // we'll release it shortly, so it's OK (?)
+
+ // is this stripe active, and within the region we're expanding?
+ if (atomic_read(&ash->count) > 0 &&
+ ash->disks == conf->previous_raid_disks &&
+ ash->sector >= first_touched_sector &&
+ ash->sector <= last_touched_sector) {
+ activity = 1;
+ break;
+ }
+ }
+ }
+
+ if (activity) {
+ spin_unlock_irq(&conf->device_lock);
+ goto please_wait;
+ }
+ }
+
+ /*
+ * Check that we have enough free stripes to write out our
+ * entire chunk in the new layout. If not, we'll have to wait
+ * until some writes have been retired. We can't just do
+ * as in get_active_stripe() and sleep here until enough are
+ * free, since all busy stripes might have STRIPE_HANDLE set
+ * and thus won't be retired until somebody (our thread!) takes
+ * care of them.
+ */
+
+ {
+ int not_enough_free = 0;
+
+ for (i = 0; i < conf->chunk_size / STRIPE_SIZE; ++i) {
+ newsh[i] = get_free_stripe(conf, 1);
+ if (newsh[i] == NULL) {
+ not_enough_free = 1;
+ break;
+ }
+ init_stripe(newsh[i], dest_sector + i * STRIPE_SECTORS, pd_idx);
+ }
+
+ if (not_enough_free) {
+ // release all the stripes we allocated
+ for (i = 0; i < conf->chunk_size / STRIPE_SIZE; ++i) {
+ if (newsh[i] == NULL)
+ break;
+ atomic_inc(&newsh[i]->count);
+ __release_stripe(conf, newsh[i]);
+ }
+ spin_unlock_irq(&conf->device_lock);
+ goto please_wait;
+ }
+ }
+
+ for (i = 0; i < conf->chunk_size / STRIPE_SIZE; ++i) {
+ for (d = 0; d < conf->raid_disks; ++d) {
+ unsigned dd_idx = d;
+
+ if (d != pd_idx) {
+ if (dd_idx > pd_idx)
+ --dd_idx;
+
+ memcpy(page_address(newsh[i]->dev[d].page), page_address(conf->expand_buffer[dd_idx * conf->chunk_size / STRIPE_SIZE + i].page), STRIPE_SIZE);
+ }
+ set_bit(R5_Wantwrite, &newsh[i]->dev[d].flags);
+ set_bit(R5_Syncio, &newsh[i]->dev[d].flags);
+ }
+ }
+
+ for (i=0; i < (conf->raid_disks - 1) * (conf->chunk_size / STRIPE_SIZE); ++i) {
+ conf->expand_buffer[i].up_to_date = 0;
+ }
+
+ conf->expand_progress += advance;
+
+ spin_unlock_irq(&conf->device_lock);
+
+ for (i = 0; i < conf->chunk_size / STRIPE_SIZE; ++i) {
+ compute_parity(newsh[i], RECONSTRUCT_WRITE);
+
+ atomic_inc(&newsh[i]->count);
+ set_bit(STRIPE_INSYNC, &newsh[i]->state);
+ set_bit(STRIPE_HANDLE, &newsh[i]->state);
+ release_stripe(newsh[i]);
+ }
+
+ spin_lock_irq(&conf->device_lock);
+ md_done_sync(conf->mddev, advance, 1);
+ wake_up(&conf->wait_for_expand_progress);
+ spin_unlock_irq(&conf->device_lock);
+
+// md_sync_acct(conf->disks[0].rdev->bdev, STRIPE_SECTORS * (conf->raid_disks - 1));
+
+ // see if we have delayed data that we can process now
+ {
+ struct list_head *l, *next;
+
+ spin_lock_irq(&conf->device_lock);
+ l = conf->wait_for_expand_list.next;
+
+// printk("printing delay list:\n");
+ while (l != &conf->wait_for_expand_list) {
+ int i, d = 0;
+ int do_process = 0;
+
+ struct stripe_head *dsh;
+ dsh = list_entry(l, struct stripe_head, lru);
+// printk("sector: %llu\n", dsh->sector);
+
+ for (i=0; i<disks; ++i) {
+ sector_t start_sector, dest_sector;
+ unsigned int dd_idx, pd_idx;
+
+ if (i == dsh->pd_idx)
+ continue;
+
+ start_sector = dsh->sector * (conf->previous_raid_disks - 1) + d * (conf->chunk_size >> 9);
+
+ // see what sector this block would land in in the new layout
+ dest_sector = raid5_compute_sector(start_sector, conf->raid_disks,
+ conf->raid_disks - 1, &dd_idx, &pd_idx, conf);
+ if (/*dest_sector * (conf->raid_disks - 1) >= conf->expand_progress &&*/
+ dest_sector * (conf->raid_disks - 1) < conf->expand_progress + (conf->raid_disks - 1) * (conf->chunk_size >> 9)) {
+ do_process = 1;
+ }
+
+ ++d;
+ }
+
+ next = l->next;
+
+ if (do_process) {
+ list_del_init(l);
+
+ set_bit(STRIPE_HANDLE, &dsh->state);
+ clear_bit(STRIPE_DELAYED, &dsh->state);
+ clear_bit(STRIPE_DELAY_EXPAND, &dsh->state);
+ atomic_inc(&dsh->count);
+ atomic_inc(&dsh->count);
+ printk("pulling in stuff from delayed, sector=%llu\n",
+ dsh->sector);
+ __release_stripe(conf, dsh);
+ } else {
+ printk("still there\n");
+ }
+
+ l = next;
+ }
+
+ spin_unlock_irq(&conf->device_lock);
+ }
+
+ // see if we are done
+ if (conf->expand_progress >= conf->mddev->array_size << 1) {
+ printk("expand done, waiting for last activity to settle...\n");
+// conf->mddev->raid_disks = conf->raid_disks;
+// raid5_resize(conf->mddev, conf->mddev->size << 1);
+ conf->expand_in_progress = 2;
+ }
+
+please_wait:
+ 1;
+ }
+
+ if (delay_to_future) { // && atomic_dec_and_test(&sh->count)) {
+ set_bit(STRIPE_DELAY_EXPAND, &sh->state);
+ }
+ }
+
/* now to consider writing and what else, if anything should be read */
if (to_write) {
int rmw=0, rcw=0;
@@ -1237,7 +1737,9 @@
}
}
if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) {
- md_done_sync(conf->mddev, STRIPE_SECTORS,1);
+ if (!conf->expand_in_progress) {
+ md_done_sync(conf->mddev, STRIPE_SECTORS,1);
+ }
clear_bit(STRIPE_SYNCING, &sh->state);
}
@@ -1279,7 +1781,7 @@
rcu_read_unlock();
if (rdev) {
- if (test_bit(R5_Syncio, &sh->dev[i].flags))
+ if (test_bit(R5_Syncio, &sh->dev[i].flags) && !conf->expand_in_progress)
md_sync_acct(rdev->bdev, STRIPE_SECTORS);
bi->bi_bdev = rdev->bdev;
@@ -1308,6 +1810,7 @@
static inline void raid5_activate_delayed(raid5_conf_t *conf)
{
+ PRINTK("raid5_activate_delayed\n");
if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
while (!list_empty(&conf->delayed_list)) {
struct list_head *l = conf->delayed_list.next;
@@ -1428,8 +1931,15 @@
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);
+ if (conf->expand_in_progress && logical_sector >= conf->expand_progress) {
+ PRINTK("GEOM: old\n");
+ new_sector = raid5_compute_sector(logical_sector,
+ conf->previous_raid_disks, conf->previous_raid_disks - 1, &dd_idx, &pd_idx, conf);
+ } else {
+ PRINTK("GEOM: new\n");
+ new_sector = raid5_compute_sector(logical_sector,
+ raid_disks, data_disks, &dd_idx, &pd_idx, conf);
+ }
PRINTK("raid5: make_request, sector %llu logical %llu\n",
(unsigned long long)new_sector,
@@ -1488,6 +1998,13 @@
int raid_disks = conf->raid_disks;
int data_disks = raid_disks-1;
+ if (conf->expand_in_progress) {
+ raid_disks = conf->previous_raid_disks;
+ data_disks = raid_disks-1;
+ }
+
+ BUG_ON(data_disks == 0 || raid_disks == 0);
+
if (sector_nr >= mddev->size <<1) {
/* just being told to finish up .. nothing much to do */
unplug_slaves(mddev);
@@ -1499,17 +2016,41 @@
*/
if (mddev->degraded >= 1 && test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
int rv = (mddev->size << 1) - sector_nr;
+ printk("md_done_sync()\n");
md_done_sync(mddev, rv, 1);
return rv;
}
+
+ /* if we're in an expand, we can't allow the process
+ * to keep reading in stripes; we might not have enough buffer
+ * space to keep it all in RAM.
+ */
+ if (conf->expand_in_progress && sector_nr >= conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1)) {
+ //printk("DELAY\n");
+ //printall(conf);
+ //printk("progress = %llu\n", conf->expand_progress);
+ spin_lock_irq(&conf->device_lock);
+ wait_event_lock_irq(conf->wait_for_expand_progress,
+ sector_nr < conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1),
+ conf->device_lock,
+ unplug_slaves(conf->mddev);
+ );
+ spin_unlock_irq(&conf->device_lock);
+ //printk("DELAY DONE\n");
+ }
x = sector_nr;
chunk_offset = sector_div(x, sectors_per_chunk);
stripe = x;
BUG_ON(x != stripe);
-
+
+ PRINTK("sync_request:%llu/%llu, %u+%u active, pr=%llu v. %llu\n", sector_nr, mddev->size<<1,
+ atomic_read(&conf->active_stripes), atomic_read(&conf->active_stripes_expand),
+ sector_nr,
+ conf->expand_progress + (conf->chunk_size >> 9) * (conf->raid_disks - 1));
+
first_sector = raid5_compute_sector((sector_t)stripe*data_disks*sectors_per_chunk
- + chunk_offset, raid_disks, data_disks, &dd_idx, &pd_idx, conf);
+ + chunk_offset, raid_disks, data_disks, &dd_idx, &pd_idx, conf);
sh = get_active_stripe(conf, sector_nr, pd_idx, 1);
if (sh == NULL) {
sh = get_active_stripe(conf, sector_nr, pd_idx, 0);
@@ -1553,18 +2094,29 @@
while (1) {
struct list_head *first;
+ conf = mddev_to_conf(mddev);
+
if (list_empty(&conf->handle_list) &&
atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD &&
!blk_queue_plugged(mddev->queue) &&
- !list_empty(&conf->delayed_list))
+ !list_empty(&conf->delayed_list)) {
+ PRINTK("activate delayed\n");
raid5_activate_delayed(conf);
+ }
if (list_empty(&conf->handle_list))
break;
first = conf->handle_list.next;
+ PRINTK("first: %p\n", first);
+
sh = list_entry(first, struct stripe_head, lru);
+#if RAID5_DEBUG
+ PRINTK("sh: %p\n", sh);
+ print_sh(sh);
+#endif
+
list_del_init(first);
atomic_inc(&sh->count);
if (atomic_read(&sh->count)!= 1)
@@ -1577,7 +2129,7 @@
spin_lock_irq(&conf->device_lock);
}
- PRINTK("%d stripes handled\n", handled);
+// PRINTK("%d stripes handled\n", handled);
spin_unlock_irq(&conf->device_lock);
@@ -1594,6 +2146,8 @@
struct disk_info *disk;
struct list_head *tmp;
+ printk("run()!\n");
+
if (mddev->level != 5 && mddev->level != 4) {
printk("raid5: %s: raid level not set to 4/5 (%d)\n", mdname(mddev), mddev->level);
return -EIO;
@@ -1650,6 +2204,7 @@
conf->level = mddev->level;
conf->algorithm = mddev->layout;
conf->max_nr_stripes = NR_STRIPES;
+ conf->expand_in_progress = 0;
/* device size must be a multiple of chunk size */
mddev->size &= ~(mddev->chunk_size/1024 -1);
@@ -1691,7 +2246,7 @@
}
memory = conf->max_nr_stripes * (sizeof(struct stripe_head) +
conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
- if (grow_stripes(conf, conf->max_nr_stripes)) {
+ if (grow_stripes(conf, conf->max_nr_stripes, 0)) {
printk(KERN_ERR
"raid5: couldn't allocate %dkB for buffers\n", memory);
shrink_stripes(conf);
@@ -1767,8 +2322,8 @@
printk("sh %llu, pd_idx %d, state %ld.\n",
(unsigned long long)sh->sector, sh->pd_idx, sh->state);
- printk("sh %llu, count %d.\n",
- (unsigned long long)sh->sector, atomic_read(&sh->count));
+ printk("sh %llu, count %d, disks %d.\n",
+ (unsigned long long)sh->sector, atomic_read(&sh->count), sh->disks);
printk("sh %llu, ", (unsigned long long)sh->sector);
for (i = 0; i < sh->raid_conf->raid_disks; i++) {
printk("(cache%d: %p %ld) ",
@@ -1865,6 +2420,9 @@
mdk_rdev_t *rdev;
struct disk_info *p = conf->disks + number;
+ printk("we were asked to remove a disk\n");
+ return -EBUSY; // sesse hack
+
print_raid5_conf(conf);
rdev = p->rdev;
if (rdev) {
@@ -1894,27 +2452,37 @@
int disk;
struct disk_info *p;
- if (mddev->degraded > 1)
+ printk("RAID5 ADD DISK PLZ: %p\n", rdev);
+
+ if (mddev->degraded > 1) {
+ printk("GAVE UP\n");
+
/* no point adding a device */
return 0;
+ }
/*
* find the disk ...
*/
- for (disk=0; disk < mddev->raid_disks; disk++)
+ for (disk=0; disk < mddev->raid_disks; disk++) {
if ((p=conf->disks + disk)->rdev == NULL) {
+ printk("adding disk to %u\n", disk);
+
+ rdev->faulty = 0;
rdev->in_sync = 0;
rdev->raid_disk = disk;
found = 1;
p->rdev = rdev;
break;
}
+ }
print_raid5_conf(conf);
return found;
}
static int raid5_resize(mddev_t *mddev, sector_t sectors)
{
+ raid5_conf_t *conf = mddev_to_conf(mddev);
/* no resync is happening, and there is enough space
* on all devices, so we can resize.
* We need to make sure resync covers any new space.
@@ -1922,8 +2490,14 @@
* any io in the removed space completes, but it hardly seems
* worth it.
*/
+ printk("asked to resize\n");
+ if (conf->expand_in_progress)
+ return -EBUSY;
+
sectors &= ~((sector_t)mddev->chunk_size/512 - 1);
+ printk("old array_size: %llu\n", mddev->array_size);
mddev->array_size = (sectors * (mddev->raid_disks-1))>>1;
+ printk("new array_size: %llu (%llu x %u)\n", mddev->array_size, sectors, mddev->raid_disks - 1);
set_capacity(mddev->gendisk, mddev->array_size << 1);
mddev->changed = 1;
if (sectors/2 > mddev->size && mddev->recovery_cp == MaxSector) {
@@ -1934,6 +2508,221 @@
return 0;
}
+static int raid5_reshape(mddev_t *mddev, int raid_disks)
+{
+ raid5_conf_t *conf = mddev_to_conf(mddev);
+ raid5_conf_t *newconf;
+ struct list_head *tmp;
+ mdk_rdev_t *rdev;
+ unsigned long flags;
+
+ int d, i;
+
+ if (mddev->degraded >= 1 || conf->expand_in_progress)
+ return -EBUSY;
+
+ printk("sesse was here: reshape to %u disks\n", raid_disks);
+ print_raid5_conf(conf);
+
+ newconf = kmalloc (sizeof (raid5_conf_t)
+ + raid_disks * sizeof(struct disk_info),
+ GFP_KERNEL);
+ if (newconf == NULL)
+ return -ENOMEM;
+
+ memset(newconf, 0, sizeof (raid5_conf_t) + raid_disks * sizeof(struct disk_info));
+ memcpy(newconf, conf, sizeof (raid5_conf_t) + conf->raid_disks * sizeof(struct disk_info));
+
+ newconf->expand_in_progress = 1;
+ newconf->expand_progress = 0;
+ newconf->raid_disks = mddev->raid_disks = raid_disks;
+ newconf->previous_raid_disks = conf->raid_disks;
+
+ INIT_LIST_HEAD(&newconf->inactive_list_expand);
+
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+ mddev->private = newconf;
+
+ printk("conf=%p newconf=%p\n", conf, newconf);
+
+ if (newconf->handle_list.next)
+ newconf->handle_list.next->prev = &newconf->handle_list;
+ if (newconf->delayed_list.next)
+ newconf->delayed_list.next->prev = &newconf->delayed_list;
+ if (newconf->inactive_list.next)
+ newconf->inactive_list.next->prev = &newconf->inactive_list;
+
+ if (newconf->handle_list.prev == &conf->handle_list)
+ newconf->handle_list.prev = &newconf->handle_list;
+ if (newconf->delayed_list.prev == &conf->delayed_list)
+ newconf->delayed_list.prev = &newconf->delayed_list;
+ if (newconf->inactive_list.prev == &conf->inactive_list)
+ newconf->inactive_list.prev = &newconf->inactive_list;
+
+ if (newconf->wait_for_stripe.task_list.prev == &conf->wait_for_stripe.task_list)
+ newconf->wait_for_stripe.task_list.prev = &newconf->wait_for_stripe.task_list;
+ if (newconf->wait_for_overlap.task_list.prev == &conf->wait_for_overlap.task_list)
+ newconf->wait_for_overlap.task_list.prev = &newconf->wait_for_overlap.task_list;
+
+ init_waitqueue_head(&newconf->wait_for_stripe_expand);
+ init_waitqueue_head(&newconf->wait_for_expand_progress);
+ INIT_LIST_HEAD(&newconf->wait_for_expand_list);
+
+ // update all the stripes
+ for (i = 0; i < NR_STRIPES; ++i) {
+ struct stripe_head *sh = newconf->stripe_hashtbl[i];
+ while (sh) {
+ sh->raid_conf = newconf;
+
+ if (sh->lru.next == &conf->inactive_list)
+ sh->lru.next = &newconf->inactive_list;
+ if (sh->lru.next == &conf->handle_list)
+ sh->lru.next = &newconf->handle_list;
+
+ sh = sh->hash_next;
+ }
+ }
+
+ // ...and all on the inactive queue
+ {
+ struct list_head *first = newconf->inactive_list.next;
+
+ while (1) {
+ struct stripe_head *sh = list_entry(first, struct stripe_head, lru);
+ sh->raid_conf = newconf;
+
+ if (sh->lru.next == &conf->inactive_list)
+ sh->lru.next = &newconf->inactive_list;
+ if (sh->lru.next == &conf->handle_list)
+ sh->lru.next = &newconf->handle_list;
+
+ if (first->next == &conf->inactive_list || first->next == &newconf->inactive_list) {
+ first->next = &newconf->inactive_list;
+ break;
+ }
+
+ first = first->next;
+ };
+ }
+
+ // update the pointer for the other lists as well
+ {
+ struct list_head *first = &newconf->handle_list;
+ while (1) {
+ if (first->next == &conf->handle_list) {
+ first->next = &newconf->handle_list;
+ break;
+ }
+
+ first = first->next;
+ };
+ }
+ {
+ struct list_head *first = &newconf->delayed_list;
+ while (1) {
+ if (first->next == &conf->delayed_list) {
+ first->next = &newconf->delayed_list;
+ break;
+ }
+
+ first = first->next;
+ };
+ }
+ {
+ struct list_head *first = &newconf->wait_for_stripe.task_list;
+ while (1) {
+ if (first->next == &conf->wait_for_stripe.task_list) {
+ first->next = &newconf->wait_for_stripe.task_list;
+ break;
+ }
+
+ first = first->next;
+ };
+ }
+ {
+ struct list_head *first = &newconf->wait_for_overlap.task_list;
+ while (1) {
+ if (first->next == &conf->wait_for_overlap.task_list) {
+ first->next = &newconf->wait_for_overlap.task_list;
+ break;
+ }
+
+ first = first->next;
+ };
+ }
+
+ ITERATE_RDEV(mddev,rdev,tmp) {
+ printk("disk: %p\n", rdev);
+ for (d= 0; d < newconf->raid_disks; d++) {
+ if (newconf->disks[d].rdev == rdev) {
+ goto already_there;
+ }
+ }
+
+ raid5_add_disk(mddev, rdev);
+ newconf->failed_disks++;
+
+already_there:
+ 1;
+ }
+
+ // argh! we can't hold this lock while allocating memory
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+
+ // allocate new stripes
+ atomic_set(&newconf->active_stripes_expand, 0);
+ if (grow_stripes(newconf, newconf->max_nr_stripes, 1)) {
+ int memory = newconf->max_nr_stripes * (sizeof(struct stripe_head) +
+ newconf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
+ printk(KERN_ERR "raid5: couldn't allocate %dkB for expand stripes\n", memory);
+ shrink_stripes(newconf);
+ kfree(newconf);
+ return -ENOMEM;
+ }
+
+ // and space for our temporary expansion buffers
+ newconf->expand_buffer = kmalloc (sizeof(struct expand_buf) * (conf->chunk_size / STRIPE_SIZE) * (raid_disks-1), GFP_KERNEL);
+ if (newconf->expand_buffer == NULL) {
+ printk(KERN_ERR "raid5: couldn't allocate %dkB for expand buffer\n",
+ (conf->chunk_size * (raid_disks-1)) >> 10);
+ shrink_stripes(newconf);
+ kfree(newconf);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < (conf->chunk_size / STRIPE_SIZE) * (raid_disks-1); ++i) {
+ newconf->expand_buffer[i].page = alloc_page(GFP_KERNEL);
+ if (newconf->expand_buffer[i].page == NULL) {
+ printk(KERN_ERR "raid5: couldn't allocate %dkB for expand buffer\n",
+ (conf->chunk_size * (raid_disks-1)) >> 10);
+ shrink_stripes(newconf);
+ kfree(newconf);
+ return -ENOMEM;
+ }
+ newconf->expand_buffer[i].up_to_date = 0;
+ }
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+
+ print_raid5_conf(newconf);
+
+ clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+ set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+ mddev->recovery_cp = 0;
+ md_wakeup_thread(mddev->thread);
+// md_check_recovery(mddev);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+
+ kfree(conf);
+
+ printk("Starting expand.\n");
+
+ return 0;
+}
+
+
static mdk_personality_t raid5_personality=
{
.name = "raid5",
@@ -1948,6 +2737,7 @@
.spare_active = raid5_spare_active,
.sync_request = sync_request,
.resize = raid5_resize,
+ .reshape = raid5_reshape
};
static int __init raid5_init (void)
diff -ur linux-2.6-2.6.12/include/linux/raid/raid5.h ../linux-2.6-2.6.12/include/linux/raid/raid5.h
--- linux-2.6-2.6.12/include/linux/raid/raid5.h 2005-06-17 21:48:29.000000000 +0200
+++ linux-2.6-2.6.12.patch/include/linux/raid/raid5.h 2005-09-17 00:47:25.000000000 +0200
@@ -92,7 +92,11 @@
* stripe is also (potentially) linked to a hash bucket in the hash
* table so that it can be found by sector number. Stripes that are
* not hashed must be on the inactive_list, and will normally be at
- * the front. All stripes start life this way.
+ * the front. All stripes start life this way. There is also a
+ * "inactive_list_expand"; this is only used during an expand, and
+ * it contains stripes with "disks" set to the correct number of disks
+ * after the expand (and with the correct amount of memory allocated,
+ * of course).
*
* The inactive_list, handle_list and hash bucket lists are all protected by the
* device_lock.
@@ -134,6 +138,7 @@
unsigned long state; /* state flags */
atomic_t count; /* nr of active thread/requests */
spinlock_t lock;
+ int disks; /* disks in stripe */
struct r5dev {
struct bio req;
struct bio_vec vec;
@@ -171,6 +176,7 @@
#define STRIPE_INSYNC 4
#define STRIPE_PREREAD_ACTIVE 5
#define STRIPE_DELAYED 6
+#define STRIPE_DELAY_EXPAND 7
/*
* Plugging:
@@ -199,6 +205,10 @@
struct disk_info {
mdk_rdev_t *rdev;
};
+struct expand_buf {
+ struct page *page;
+ int up_to_date;
+};
struct raid5_private_data {
struct stripe_head **stripe_hashtbl;
@@ -208,22 +218,38 @@
int raid_disks, working_disks, failed_disks;
int max_nr_stripes;
+ /* used during an expand */
+ int expand_in_progress;
+ sector_t expand_progress;
+ int previous_raid_disks;
+ struct list_head wait_for_expand_list;
+
+ struct expand_buf *expand_buffer;
+
struct list_head handle_list; /* stripes needing handling */
struct list_head delayed_list; /* stripes that have plugged requests */
atomic_t preread_active_stripes; /* stripes with scheduled io */
char cache_name[20];
+ char cache_name_expand[20];
kmem_cache_t *slab_cache; /* for allocating stripes */
+ kmem_cache_t *slab_cache_expand;
+
/*
* Free stripes pool
*/
atomic_t active_stripes;
+ atomic_t active_stripes_expand;
struct list_head inactive_list;
+ struct list_head inactive_list_expand;
wait_queue_head_t wait_for_stripe;
+ wait_queue_head_t wait_for_stripe_expand;
+ wait_queue_head_t wait_for_expand_progress;
wait_queue_head_t wait_for_overlap;
int inactive_blocked; /* release of inactive stripes blocked,
* waiting for 25% to be free
- */
+ */
+ int inactive_blocked_expand;
spinlock_t device_lock;
struct disk_info disks[0];
};
