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>

1 files changed, 11 insertions, 17 deletions

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 280b6b060d53..cae43333ef16 100644
--- 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;