NFSv4.1/flexfiles: Mark layout for return if the mirrors are invalid

If a read-write layout has an invalid mirror, then we should
mark it as invalid, and return it.
If a read-only layout has an invalid mirror, then mark it as invalid
and check if there is still at least one valid mirror before we return
it.

Note: Also fix incorrect use of pnfs_generic_mark_devid_invalid().
We really want nfs4_mark_deviceid_unavailable().
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/flexfilelayout/flexfilelayoutdev.c

@@ -172,6 +172,32 @@ nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 	return NULL;
 }
 
+static void ff_layout_mark_devid_invalid(struct pnfs_layout_segment *lseg,
+		struct nfs4_deviceid_node *devid)
+{
+	nfs4_mark_deviceid_unavailable(devid);
+	if (!ff_layout_has_available_ds(lseg))
+		pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
+				lseg);
+}
+
+static bool ff_layout_mirror_valid(struct pnfs_layout_segment *lseg,
+		struct nfs4_ff_layout_mirror *mirror)
+{
+	if (mirror == NULL || mirror->mirror_ds == NULL) {
+		pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
+					lseg);
+		return false;
+	}
+	if (mirror->mirror_ds->ds == NULL) {
+		struct nfs4_deviceid_node *devid;
+		devid = &mirror->mirror_ds->id_node;
+		ff_layout_mark_devid_invalid(lseg, devid);
+		return false;
+	}
+	return true;
+}
+
 static u64
 end_offset(u64 start, u64 len)
 {
@@ -336,16 +362,10 @@ nfs4_ff_layout_select_ds_fh(struct pnfs_layout_segment *lseg, u32 mirror_idx)
 {
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, mirror_idx);
 	struct nfs_fh *fh = NULL;
-	struct nfs4_deviceid_node *devid;
 
-	if (mirror == NULL || mirror->mirror_ds == NULL ||
-	    mirror->mirror_ds->ds == NULL) {
-		printk(KERN_ERR "NFS: %s: No data server for mirror offset index %d\n",
+	if (!ff_layout_mirror_valid(lseg, mirror)) {
+		pr_err_ratelimited("NFS: %s: No data server for mirror offset index %d\n",
 			__func__, mirror_idx);
-		if (mirror && mirror->mirror_ds) {
-			devid = &mirror->mirror_ds->id_node;
-			nfs4_mark_deviceid_unavailable(devid);
-		}
 		goto out;
 	}
 
@@ -368,14 +388,9 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
 	unsigned int max_payload;
 	rpc_authflavor_t flavor;
 
-	if (mirror == NULL || mirror->mirror_ds == NULL ||
-	    mirror->mirror_ds->ds == NULL) {
-		printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
+	if (!ff_layout_mirror_valid(lseg, mirror)) {
+		pr_err_ratelimited("NFS: %s: No data server for offset index %d\n",
 			__func__, ds_idx);
-		if (mirror && mirror->mirror_ds) {
-			devid = &mirror->mirror_ds->id_node;
-			nfs4_mark_deviceid_unavailable(devid);
-		}
 		goto out;
 	}