nfs: add mirroring support to pgio layer
This patch adds mirrored write support to the pgio layer. The default
is to use one mirror, but pgio callers may define callbacks to change
this to any value up to the (arbitrarily selected) limit of 16.
The basic idea is to break out members of nfs_pageio_descriptor that cannot
be shared between mirrored DSes and put them in a new structure.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 5bc99f0..6400a1e 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1329,6 +1329,7 @@
struct nfs_page_array page_array;
struct nfs_client *ds_clp; /* pNFS data server */
int ds_commit_idx; /* ds index if ds_clp is set */
+ int pgio_mirror_idx;/* mirror index in pgio layer */
};
struct nfs_mds_commit_info {