NFSv4.1/pNFS: Ensure we enforce RFC5661 Section 12.5.5.2.1
The RFC requires us to check if the server is recalling a stateid that we
haven't yet received. If so, tell it to wait.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 34852ec..1b24ad0 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -160,6 +160,22 @@
return lo;
}
+/*
+ * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
+ */
+static bool pnfs_check_stateid_sequence(struct pnfs_layout_hdr *lo,
+ const nfs4_stateid *new)
+{
+ u32 oldseq, newseq;
+
+ oldseq = be32_to_cpu(lo->plh_stateid.seqid);
+ newseq = be32_to_cpu(new->seqid);
+
+ if (newseq > oldseq + 1)
+ return false;
+ return true;
+}
+
static u32 initiate_file_draining(struct nfs_client *clp,
struct cb_layoutrecallargs *args)
{
@@ -175,6 +191,10 @@
ino = lo->plh_inode;
spin_lock(&ino->i_lock);
+ if (!pnfs_check_stateid_sequence(lo, &args->cbl_stateid)) {
+ rv = NFS4ERR_DELAY;
+ goto unlock;
+ }
pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
spin_unlock(&ino->i_lock);