NFS41: pop some layoutget errors to application

For ERESTARTSYS/EIO/EROFS/ENOSPC/E2BIG in layoutget, we
should just bail out instead of hiding the error and
retrying inband IO.

Change all the call sites to pop the error all the way up.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 6095a8d..b1acc41 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -906,14 +906,15 @@
 
 	if (IS_ERR(lseg)) {
 		switch (PTR_ERR(lseg)) {
-		case -ENOMEM:
 		case -ERESTARTSYS:
+		case -EIO:
+		case -ENOSPC:
+		case -EROFS:
+		case -E2BIG:
 			break;
 		default:
-			/* remember that LAYOUTGET failed and suspend trying */
-			pnfs_layout_io_set_failed(lo, range->iomode);
+			return NULL;
 		}
-		return NULL;
 	} else
 		pnfs_layout_clear_fail_bit(lo,
 				pnfs_iomode_to_fail_bit(range->iomode));
@@ -1649,7 +1650,7 @@
 			"(%s, offset: %llu, length: %llu)\n",
 			__func__, ino->i_sb->s_id,
 			(unsigned long long)NFS_FILEID(ino),
-			lseg == NULL ? "not found" : "found",
+			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
 			iomode==IOMODE_RW ?  "read/write" : "read-only",
 			(unsigned long long)pos,
 			(unsigned long long)count);
@@ -1828,6 +1829,11 @@
 						   rd_size,
 						   IOMODE_READ,
 						   GFP_KERNEL);
+		if (IS_ERR(pgio->pg_lseg)) {
+			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
+			pgio->pg_lseg = NULL;
+			return;
+		}
 	}
 	/* If no lseg, fall back to read through mds */
 	if (pgio->pg_lseg == NULL)
@@ -1840,13 +1846,19 @@
 pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
 			   struct nfs_page *req, u64 wb_size)
 {
-	if (pgio->pg_lseg == NULL)
+	if (pgio->pg_lseg == NULL) {
 		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 						   req->wb_context,
 						   req_offset(req),
 						   wb_size,
 						   IOMODE_RW,
 						   GFP_NOFS);
+		if (IS_ERR(pgio->pg_lseg)) {
+			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
+			pgio->pg_lseg = NULL;
+			return;
+		}
+	}
 	/* If no lseg, fall back to write through mds */
 	if (pgio->pg_lseg == NULL)
 		nfs_pageio_reset_write_mds(pgio);