pNFS/flexfiles: ff_layout_pg_init_read should exit on error

If we get an error while retrieving the layout, then we should
report it rather than falling back to I/O through the MDS.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 280b6b0..cae4333 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -812,7 +812,6 @@ ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
                      struct nfs_page *req,
                      bool strict_iomode)
 {
-retry_strict:
        pnfs_put_lseg(pgio->pg_lseg);
        pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
                                           req->wb_context,
@@ -825,16 +824,6 @@ retry_strict:
                pgio->pg_error = PTR_ERR(pgio->pg_lseg);
                pgio->pg_lseg = NULL;
        }
-
-       /* If we don't have checking, do get a IOMODE_RW
-        * segment, and the server wants to avoid READs
-        * there, then retry!
-        */
-       if (pgio->pg_lseg && !strict_iomode &&
-           ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
-               strict_iomode = true;
-               goto retry_strict;
-       }
 }
 
 static void
@@ -849,14 +838,16 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 retry:
        pnfs_generic_pg_check_layout(pgio);
        /* Use full layout for now */
-       if (!pgio->pg_lseg)
+       if (!pgio->pg_lseg) {
                ff_layout_pg_get_read(pgio, req, false);
-       else if (ff_layout_avoid_read_on_rw(pgio->pg_lseg))
+               if (!pgio->pg_lseg)
+                       goto out_nolseg;
+       }
+       if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
                ff_layout_pg_get_read(pgio, req, true);
-
-       /* If no lseg, fall back to read through mds */
-       if (pgio->pg_lseg == NULL)
-               goto out_mds;
+               if (!pgio->pg_lseg)
+                       goto out_nolseg;
+       }
 
        ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
        if (!ds) {
@@ -878,6 +869,9 @@ retry:
        pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 
        return;
+out_nolseg:
+       if (pgio->pg_error < 0)
+               return;
 out_mds:
        pnfs_put_lseg(pgio->pg_lseg);
        pgio->pg_lseg = NULL;