Support resize is a little complex for clustered
raid, since we need to ensure all the nodes share
the same knowledge about the size of raid.
We achieve the goal by check the sync_size which
is in each node's bitmap, we can only change the
capacity after cluster_check_sync_size returns 0.
Also, get_bitmap_from_slot is added to get a slot's
bitmap. And we exported some funcs since they are
used in cluster_check_sync_size().
We can also reuse get_bitmap_from_slot to remove
redundant code existed in bitmap_copy_from_slot.
Reviewed-by: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx>
---
drivers/md/bitmap.c | 41 ++++++++++++++++++++++++---------
drivers/md/bitmap.h | 2 ++
drivers/md/md-cluster.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 93 insertions(+), 10 deletions(-)
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 9fb2ccac958a..b6fa55a3cff8 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -471,6 +471,7 @@ void bitmap_update_sb(struct bitmap *bitmap)
kunmap_atomic(sb);
write_page(bitmap, bitmap->storage.sb_page, 1);
}
+EXPORT_SYMBOL(bitmap_update_sb);
/* print out the bitmap file superblock */
void bitmap_print_sb(struct bitmap *bitmap)
@@ -1727,7 +1728,7 @@ void bitmap_flush(struct mddev *mddev)
/*
* free memory that was allocated
*/
-static void bitmap_free(struct bitmap *bitmap)
+void bitmap_free(struct bitmap *bitmap)
{
unsigned long k, pages;
struct bitmap_page *bp;
@@ -1761,6 +1762,7 @@ static void bitmap_free(struct bitmap *bitmap)
kfree(bp);
kfree(bitmap);
}
+EXPORT_SYMBOL(bitmap_free);
void bitmap_destroy(struct mddev *mddev)
{
@@ -1920,6 +1922,27 @@ int bitmap_load(struct mddev *mddev)
}
EXPORT_SYMBOL_GPL(bitmap_load);
+struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot)
+{
+ int rv = 0;
+ struct bitmap *bitmap;
+
+ bitmap = bitmap_create(mddev, slot);
+ if (IS_ERR(bitmap)) {
+ rv = PTR_ERR(bitmap);
+ return ERR_PTR(rv);
+ }
+
+ rv = bitmap_init_from_disk(bitmap, 0);
+ if (rv) {
+ bitmap_free(bitmap);
+ return ERR_PTR(rv);
+ }
+
+ return bitmap;
+}
+EXPORT_SYMBOL(get_bitmap_from_slot);
+
/* Loads the bitmap associated with slot and copies the resync information
* to our bitmap
*/
@@ -1929,14 +1952,13 @@ int bitmap_copy_from_slot(struct mddev *mddev, int slot,
int rv = 0, i, j;
sector_t block, lo = 0, hi = 0;
struct bitmap_counts *counts;
- struct bitmap *bitmap = bitmap_create(mddev, slot);
-
- if (IS_ERR(bitmap))
- return PTR_ERR(bitmap);
+ struct bitmap *bitmap;
- rv = bitmap_init_from_disk(bitmap, 0);
- if (rv)
- goto err;
+ bitmap = get_bitmap_from_slot(mddev, slot);
+ if (IS_ERR(bitmap)) {
+ pr_err("%s can't get bitmap from slot %d\n", __func__, slot);
+ return -1;
+ }
counts = &bitmap->counts;
for (j = 0; j < counts->chunks; j++) {
@@ -1963,8 +1985,7 @@ int bitmap_copy_from_slot(struct mddev *mddev, int slot,
bitmap_unplug(mddev->bitmap);
*low = lo;
*high = hi;
-err:
- bitmap_free(bitmap);
+
return rv;
}
EXPORT_SYMBOL_GPL(bitmap_copy_from_slot);
diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index 5b6dd63dda91..9f761097aab2 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h
@@ -267,8 +267,10 @@ void bitmap_daemon_work(struct mddev *mddev);
int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
int chunksize, int init);
+struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
int bitmap_copy_from_slot(struct mddev *mddev, int slot,
sector_t *lo, sector_t *hi, bool clear_bits);
+void bitmap_free(struct bitmap *bitmap);
#endif
#endif
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 8b7d55bf5aa2..5a42fc5202ff 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -1091,6 +1091,66 @@ static void metadata_update_cancel(struct mddev *mddev)
unlock_comm(cinfo);
}
+/*
+ * retun 0 if all the bitmaps have the same sync_size
+ */
+int cluster_check_sync_size(struct mddev *mddev)
+{
+ int i, rv;
+ bitmap_super_t *sb;
+ unsigned long my_sync_size, sync_size = 0;
+ int node_num = mddev->bitmap_info.nodes;
+ int current_slot = md_cluster_ops->slot_number(mddev);
+ struct bitmap *bitmap = mddev->bitmap;
+ char str[64];
+ struct dlm_lock_resource *bm_lockres;
+
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ my_sync_size = sb->sync_size;
+ kunmap_atomic(sb);
+
+ for (i = 0; i < node_num; i++) {
+ if (i == current_slot)
+ continue;
+
+ bitmap = get_bitmap_from_slot(mddev, i);
+ if (IS_ERR(bitmap)) {
+ pr_err("can't get bitmap from slot %d\n", i);
+ return -1;
+ }
+
+ /*
+ * If we can hold the bitmap lock of one node then
+ * the slot is not occupied, update the sb.
+ */
+ snprintf(str, 64, "bitmap%04d", i);
+ bm_lockres = lockres_init(mddev, str, NULL, 1);
+ if (!bm_lockres) {
+ pr_err("md-cluster: Cannot initialize %s\n", str);
+ lockres_free(bm_lockres);
+ return -ENOMEM;
+ }
+ bm_lockres->flags |= DLM_LKF_NOQUEUE;
+ rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
+ if (!rv)
+ bitmap_update_sb(bitmap);
+ lockres_free(bm_lockres);
+
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ if (sync_size == 0)
+ sync_size = sb->sync_size;
+ else if (sync_size != sb->sync_size) {
+ kunmap_atomic(sb);
+ bitmap_free(bitmap);
+ return -1;
+ }
+ kunmap_atomic(sb);
+ bitmap_free(bitmap);
+ }
+
+ return (my_sync_size == sync_size) ? 0 : -1;
+}
+
static int resync_start(struct mddev *mddev)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
--
2.6.2
--
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