md/raid10: prepare data structures for handling replacement.
Allow each slot in the RAID10 to have 2 devices, the want_replacement
and the replacement.
Also an r10bio to have 2 bios, and for resync/recovery allocate the
second bio if there are any replacement devices.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index f5088dd..9722065 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -73,7 +73,8 @@
struct r10conf *conf = data;
int size = offsetof(struct r10bio, devs[conf->copies]);
- /* allocate a r10bio with room for raid_disks entries in the bios array */
+ /* allocate a r10bio with room for raid_disks entries in the
+ * bios array */
return kzalloc(size, gfp_flags);
}
@@ -123,12 +124,19 @@
if (!bio)
goto out_free_bio;
r10_bio->devs[j].bio = bio;
+ if (!conf->have_replacement)
+ continue;
+ bio = bio_kmalloc(gfp_flags, RESYNC_PAGES);
+ if (!bio)
+ goto out_free_bio;
+ r10_bio->devs[j].repl_bio = bio;
}
/*
* Allocate RESYNC_PAGES data pages and attach them
* where needed.
*/
for (j = 0 ; j < nalloc; j++) {
+ struct bio *rbio = r10_bio->devs[j].repl_bio;
bio = r10_bio->devs[j].bio;
for (i = 0; i < RESYNC_PAGES; i++) {
if (j == 1 && !test_bit(MD_RECOVERY_SYNC,
@@ -143,6 +151,8 @@
goto out_free_pages;
bio->bi_io_vec[i].bv_page = page;
+ if (rbio)
+ rbio->bi_io_vec[i].bv_page = page;
}
}
@@ -156,8 +166,11 @@
safe_put_page(r10_bio->devs[j].bio->bi_io_vec[i].bv_page);
j = -1;
out_free_bio:
- while ( ++j < nalloc )
+ while (++j < nalloc) {
bio_put(r10_bio->devs[j].bio);
+ if (r10_bio->devs[j].repl_bio)
+ bio_put(r10_bio->devs[j].repl_bio);
+ }
r10bio_pool_free(r10_bio, conf);
return NULL;
}
@@ -178,6 +191,9 @@
}
bio_put(bio);
}
+ bio = r10bio->devs[j].repl_bio;
+ if (bio)
+ bio_put(bio);
}
r10bio_pool_free(r10bio, conf);
}
@@ -191,6 +207,10 @@
if (!BIO_SPECIAL(*bio))
bio_put(*bio);
*bio = NULL;
+ bio = &r10_bio->devs[i].repl_bio;
+ if (r10_bio->read_slot < 0 && !BIO_SPECIAL(*bio))
+ bio_put(*bio);
+ *bio = NULL;
}
}
@@ -275,19 +295,27 @@
* Find the disk number which triggered given bio
*/
static int find_bio_disk(struct r10conf *conf, struct r10bio *r10_bio,
- struct bio *bio, int *slotp)
+ struct bio *bio, int *slotp, int *replp)
{
int slot;
+ int repl = 0;
- for (slot = 0; slot < conf->copies; slot++)
+ for (slot = 0; slot < conf->copies; slot++) {
if (r10_bio->devs[slot].bio == bio)
break;
+ if (r10_bio->devs[slot].repl_bio == bio) {
+ repl = 1;
+ break;
+ }
+ }
BUG_ON(slot == conf->copies);
update_head_pos(slot, r10_bio);
if (slotp)
*slotp = slot;
+ if (replp)
+ *replp = repl;
return r10_bio->devs[slot].devnum;
}
@@ -368,7 +396,7 @@
struct r10conf *conf = r10_bio->mddev->private;
int slot;
- dev = find_bio_disk(conf, r10_bio, bio, &slot);
+ dev = find_bio_disk(conf, r10_bio, bio, &slot, NULL);
/*
* this branch is our 'one mirror IO has finished' event handler:
@@ -1025,6 +1053,7 @@
*/
plugged = mddev_check_plugged(mddev);
+ r10_bio->read_slot = -1; /* make sure repl_bio gets freed */
raid10_find_phys(conf, r10_bio);
retry_write:
blocked_rdev = NULL;
@@ -1431,7 +1460,7 @@
struct r10conf *conf = r10_bio->mddev->private;
int d;
- d = find_bio_disk(conf, r10_bio, bio, NULL);
+ d = find_bio_disk(conf, r10_bio, bio, NULL, NULL);
if (test_bit(BIO_UPTODATE, &bio->bi_flags))
set_bit(R10BIO_Uptodate, &r10_bio->state);
@@ -1493,7 +1522,7 @@
int bad_sectors;
int slot;
- d = find_bio_disk(conf, r10_bio, bio, &slot);
+ d = find_bio_disk(conf, r10_bio, bio, &slot, NULL);
if (!uptodate) {
set_bit(WriteErrorSeen, &conf->mirrors[d].rdev->flags);
@@ -2271,9 +2300,14 @@
static int init_resync(struct r10conf *conf)
{
int buffs;
+ int i;
buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
BUG_ON(conf->r10buf_pool);
+ conf->have_replacement = 0;
+ for (i = 0; i < conf->raid_disks; i++)
+ if (conf->mirrors[i].replacement)
+ conf->have_replacement = 1;
conf->r10buf_pool = mempool_create(buffs, r10buf_pool_alloc, r10buf_pool_free, conf);
if (!conf->r10buf_pool)
return -ENOMEM;