[Drbd-dev] [PATCH] drbd: fix zero metadata limit by misaligned with page size

[Nick Wang]

Metadata is aligned on 4k blocks, which is ok for x86 platform.
But may cause a result of zero page with PPC64LE or ARM with
64k page size.

And calculate effective bytes directly from sector size.

Error log:
...
drbd0: Device size clipped from 2097016s to 0s due to metadata size
...

Signed-off-by: Nick Wang <nwang at suse.com>

CC: drbd-dev at lists.linbit.com

---
 drbd/drbd_main.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drbd/drbd_main.c b/drbd/drbd_main.c
index a7294639..336a4177 100644
--- a/drbd/drbd_main.c
+++ b/drbd/drbd_main.c
@@ -5589,8 +5589,7 @@ u64 directly_connected_nodes(struct drbd_resource *resource, enum which_state wh
 
 static sector_t bm_sect_to_max_capacity(unsigned int bm_max_peers, sector_t bm_sect)
 {
-	u64 bm_pages = bm_sect >> (PAGE_SHIFT - SECTOR_SHIFT);
-	u64 bm_bytes = bm_pages << PAGE_SHIFT;
+	u64 bm_bytes = bm_sect << SECTOR_SHIFT;
 	u64 bm_bytes_per_peer = div_u64(bm_bytes, bm_max_peers);
 	u64 bm_bits_per_peer = bm_bytes_per_peer * BITS_PER_BYTE;
 	return BM_BIT_TO_SECT(bm_bits_per_peer);
-- 
2.16.4