Hi Neil,

On 02/22/2015 07:38 PM, NeilBrown wrote:

On Thu, 18 Dec 2014 10:15:23 -0600 Goldwyn Rodrigues [off-list ref] wrote:

quoted

Signed-off-by: Goldwyn Rodrigues <redacted>
---
  drivers/md/bitmap.h | 5 +++--
  1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index 30210b9..6872945 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h

@@ -128,10 +128,11 @@ typedef struct bitmap_super_s {
  	__le32 chunksize;    /* 52  the bitmap chunk size in bytes */
  	__le32 daemon_sleep; /* 56  seconds between disk flushes */
  	__le32 write_behind; /* 60  number of outstanding write-behind writes */
-	__le32 sectors_reserved; /* 64 number of 512-byte sectors that are
+	__le32 nodes;        /* 64 the maximum number of nodes in cluster. */
+	__le32 sectors_reserved; /* 68 number of 512-byte sectors that are
  				  * reserved for the bitmap. */

-	__u8  pad[256 - 68]; /* set to zero */
+	__u8  pad[256 - 72]; /* set to zero */
  } bitmap_super_t;

  /* notes:

Hi Goldwyn,
  I was reviewing you latest series to make sure it wouldn't affect the
  non-clustered use case at all, and I found this.  I really should have
  noticed it earlier....

  You are changing the location of 'sectors_reserved' in the bitmap superblock.
  That obviously cannot be allowed - new fields must always be added to the
  end.

Oops. Sorry.

  Can you update the series in git to fix that please?  Then I will pull it in
  for -next.

I have done this and re-tested. However, I also rebased against 
upstream. There were some conflicts with respect to md_personality. I 
have re-done those patches, but it would be worth a second look. The one 
which may need special review attention is "bitmap_create returns bitmap 
pointer"


Regards,

-- 
Goldwyn