NFS/flexfile: Simplify nfs4_ff_layout_select_ds_stateid()

Pass in a pointer to the mirror rather than forcing another
array access.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1799,9 +1799,7 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
 	if (fh)
 		hdr->args.fh = fh;
 
-	if (vers == 4 &&
-		!nfs4_ff_layout_select_ds_stateid(lseg, idx, &hdr->args.stateid))
-		goto out_failed;
+	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,
@@ -1867,9 +1865,7 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	if (fh)
 		hdr->args.fh = fh;
 
-	if (vers == 4 &&
-		!nfs4_ff_layout_select_ds_stateid(lseg, idx, &hdr->args.stateid))
-		goto out_failed;
+	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
 
 	/*
 	 * Note that if we ever decide to split across DSes,

fs/nfs/flexfilelayout/flexfilelayout.h

@@ -204,9 +204,8 @@ unsigned int ff_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo,
 		unsigned int maxnum);
 struct nfs_fh *
 nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror);
-int
-nfs4_ff_layout_select_ds_stateid(struct pnfs_layout_segment *lseg,
-				u32 mirror_idx,
+void
+nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
 		nfs4_stateid *stateid);
 
 struct nfs4_pnfs_ds *

fs/nfs/flexfilelayout/flexfilelayoutdev.c

@@ -357,23 +357,12 @@ nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror)
 	return &mirror->fh_versions[0];
 }
 
-int
-nfs4_ff_layout_select_ds_stateid(struct pnfs_layout_segment *lseg,
-				u32 mirror_idx,
+void
+nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
 		nfs4_stateid *stateid)
 {
-	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, mirror_idx);
-
-	if (!ff_layout_mirror_valid(lseg, mirror, false)) {
-		pr_err_ratelimited("NFS: %s: No data server for mirror offset index %d\n",
-			__func__, mirror_idx);
-		goto out;
-	}
-
+	if (nfs4_ff_layout_ds_version(mirror) == 4)
 		nfs4_stateid_copy(stateid, &mirror->stateid);
-	return 1;
-out:
-	return 0;
 }
 
 /**