NFS: change stateid to be a union
In NFSv4.1 the stateid consists of the other and seqid fields. For layout
processing we need to numerically compare the seqid value of layout stateids.
To do so, introduce a union to nfs4_stateid to switch between opaque(16 bytes)
and opaque(12 bytes) / __be32
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 930d10f..2950fca 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -118,11 +118,11 @@
if (delegation == NULL)
return 0;
- /* seqid is 4-bytes long */
- if (((u32 *) &stateid->data)[0] != 0)
+ if (stateid->stateid.seqid != 0)
return 0;
- if (memcmp(&delegation->stateid.data[4], &stateid->data[4],
- sizeof(stateid->data)-4))
+ if (memcmp(&delegation->stateid.stateid.other,
+ &stateid->stateid.other,
+ NFS4_STATEID_OTHER_SIZE))
return 0;
return 1;
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 6c0406e..34da324 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -17,7 +17,9 @@
#define NFS4_BITMAP_SIZE 2
#define NFS4_VERIFIER_SIZE 8
-#define NFS4_STATEID_SIZE 16
+#define NFS4_STATEID_SEQID_SIZE 4
+#define NFS4_STATEID_OTHER_SIZE 12
+#define NFS4_STATEID_SIZE (NFS4_STATEID_SEQID_SIZE + NFS4_STATEID_OTHER_SIZE)
#define NFS4_FHSIZE 128
#define NFS4_MAXPATHLEN PATH_MAX
#define NFS4_MAXNAMLEN NAME_MAX
@@ -167,7 +169,16 @@
};
typedef struct { char data[NFS4_VERIFIER_SIZE]; } nfs4_verifier;
-typedef struct { char data[NFS4_STATEID_SIZE]; } nfs4_stateid;
+
+struct nfs41_stateid {
+ __be32 seqid;
+ char other[NFS4_STATEID_OTHER_SIZE];
+} __attribute__ ((packed));
+
+typedef union {
+ char data[NFS4_STATEID_SIZE];
+ struct nfs41_stateid stateid;
+} nfs4_stateid;
enum nfs_opnum4 {
OP_ACCESS = 3,