Introduce md_cluster_info

md_cluster_info stores the cluster information in the MD device.

The join() is called when mddev detects it is a clustered device.
The main responsibilities are:
	1. Setup a DLM lockspace
	2. Setup all initial locks such as super block locks and bitmap lock (will come later)

The leave() clears up the lockspace and all the locks held.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 3a5767968ba0..e2aacca46911 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -433,6 +433,7 @@ void bitmap_update_sb(struct bitmap *bitmap)
         /* This might have been changed by a reshape */
         sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
         sb->chunksize = cpu_to_le32(bitmap->mddev->bitmap_info.chunksize);
+        sb->nodes = cpu_to_le32(bitmap->mddev->bitmap_info.nodes);
         sb->sectors_reserved = cpu_to_le32(bitmap->mddev->
                                            bitmap_info.space);
         kunmap_atomic(sb);
@@ -544,6 +545,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
         bitmap_super_t *sb;
         unsigned long chunksize, daemon_sleep, write_behind;
         unsigned long long events;
+        int nodes = 0;
         unsigned long sectors_reserved = 0;
         int err = -EINVAL;
         struct page *sb_page;
@@ -583,6 +585,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
         daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
         write_behind = le32_to_cpu(sb->write_behind);
         sectors_reserved = le32_to_cpu(sb->sectors_reserved);
+        nodes = le32_to_cpu(sb->nodes);
 
         /* verify that the bitmap-specific fields are valid */
         if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
@@ -643,6 +646,7 @@ out_no_sb:
         bitmap->mddev->bitmap_info.chunksize = chunksize;
         bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
         bitmap->mddev->bitmap_info.max_write_behind = write_behind;
+        bitmap->mddev->bitmap_info.nodes = nodes;
         if (bitmap->mddev->bitmap_info.space == 0 ||
             bitmap->mddev->bitmap_info.space > sectors_reserved)
                 bitmap->mddev->bitmap_info.space = sectors_reserved;
@@ -2186,6 +2190,8 @@ __ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
 
 static ssize_t metadata_show(struct mddev *mddev, char *page)
 {
+        if (mddev_is_clustered(mddev))
+                return sprintf(page, "clustered\n");
         return sprintf(page, "%s\n", (mddev->bitmap_info.external
                                       ? "external" : "internal"));
 }
@@ -2198,7 +2204,8 @@ static ssize_t metadata_store(struct mddev *mddev, const char *buf, size_t len)
                 return -EBUSY;
         if (strncmp(buf, "external", 8) == 0)
                 mddev->bitmap_info.external = 1;
-        else if (strncmp(buf, "internal", 8) == 0)
+        else if ((strncmp(buf, "internal", 8) == 0) ||
+                        (strncmp(buf, "clustered", 9) == 0))
                 mddev->bitmap_info.external = 0;
         else
                 return -EINVAL;