pNFS/flexfiles: Ensure we initialise the mirror bsizes correctly on read

[ Upstream commit ee15c7b53e52fb04583f734461244c4dcca828fa ]

While it is true that reading from an unmirrored source always uses
index 0, that is no longer true for mirrored sources when we fail over.

Fixes: 563c53e73b8b ("NFS: Fix flexfiles read failover")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 048272d60a16506c3d4f8bb8a22ff4f75eebeb1e..f9348ed1bcdad05d8bd56e69cc7bea0a0529be08 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -838,6 +838,7 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
        struct nfs4_ff_layout_mirror *mirror;
        struct nfs4_pnfs_ds *ds;
        int ds_idx;
+       u32 i;
 
 retry:
        ff_layout_pg_check_layout(pgio, req);
@@ -864,14 +865,14 @@ retry:
                goto retry;
        }
 
-       mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
+       for (i = 0; i < pgio->pg_mirror_count; i++) {
+               mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
+               pgm = &pgio->pg_mirrors[i];
+               pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
+       }
 
        pgio->pg_mirror_idx = ds_idx;
 
-       /* read always uses only one mirror - idx 0 for pgio layer */
-       pgm = &pgio->pg_mirrors[0];
-       pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
-
        if (NFS_SERVER(pgio->pg_inode)->flags &
                        (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
                pgio->pg_maxretrans = io_maxretrans;