nfsd: be more systematic about selecting error codes for internal use.

Rather than using ad hoc values for internal errors (30000, 11000, ...)
use 'enum' to sequentially allocate numbers starting from the first
known available number - now visible as NFS4ERR_FIRST_FREE.

The goal is values that are distinct from all be32 error codes.  To get
those we must first select integers that are not already used, then
convert them with cpu_to_be32().

Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 8750ade0a7ee4084b76dd2f6189f6d51902ef817..11825cbe4360906d42949e2ff4f3834d70baa205 100644 (file)
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -330,17 +330,31 @@ void              nfsd_lockd_shutdown(void);
 #define nfserr_xattr2big               cpu_to_be32(NFS4ERR_XATTR2BIG)
 #define nfserr_noxattr                 cpu_to_be32(NFS4ERR_NOXATTR)
 
-/* error codes for internal use */
+/*
+ * Error codes for internal use.  We use enum to choose numbers that are
+ * not already assigned, then covert to be32 resulting in a number that
+ * cannot conflict with any existing be32 nfserr value.
+ */
+enum {
+       NFSERR_DROPIT = NFS4ERR_FIRST_FREE,
 /* if a request fails due to kmalloc failure, it gets dropped.
  *  Client should resend eventually
  */
-#define        nfserr_dropit           cpu_to_be32(30000)
+#define        nfserr_dropit           cpu_to_be32(NFSERR_DROPIT)
+
 /* end-of-file indicator in readdir */
-#define        nfserr_eof              cpu_to_be32(30001)
+       NFSERR_EOF,
+#define        nfserr_eof              cpu_to_be32(NFSERR_EOF)
+
 /* replay detected */
-#define        nfserr_replay_me        cpu_to_be32(11001)
+       NFSERR_REPLAY_ME,
+#define        nfserr_replay_me        cpu_to_be32(NFSERR_REPLAY_ME)
+
 /* nfs41 replay detected */
-#define        nfserr_replay_cache     cpu_to_be32(11002)
+       NFSERR_REPLAY_CACHE,
+#define        nfserr_replay_cache     cpu_to_be32(NFSERR_REPLAY_CACHE)
+
+};
 
 /* Check for dir entries '.' and '..' */
 #define isdotent(n, l) (l < 3 && n[0] == '.' && (l == 1 || n[1] == '.'))

diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index f9df88091c6d7077f9cbefeff09cbbe135142e69..8d7430d9f2183f08fc995b12370d0ddddf0bffba 100644 (file)
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -281,15 +281,18 @@ enum nfsstat4 {
        /* nfs42 */
        NFS4ERR_PARTNER_NOTSUPP = 10088,
        NFS4ERR_PARTNER_NO_AUTH = 10089,
-       NFS4ERR_UNION_NOTSUPP = 10090,
-       NFS4ERR_OFFLOAD_DENIED = 10091,
-       NFS4ERR_WRONG_LFS = 10092,
-       NFS4ERR_BADLABEL = 10093,
-       NFS4ERR_OFFLOAD_NO_REQS = 10094,
+       NFS4ERR_UNION_NOTSUPP   = 10090,
+       NFS4ERR_OFFLOAD_DENIED  = 10091,
+       NFS4ERR_WRONG_LFS       = 10092,
+       NFS4ERR_BADLABEL        = 10093,
+       NFS4ERR_OFFLOAD_NO_REQS = 10094,
 
        /* xattr (RFC8276) */
-       NFS4ERR_NOXATTR        = 10095,
-       NFS4ERR_XATTR2BIG      = 10096,
+       NFS4ERR_NOXATTR         = 10095,
+       NFS4ERR_XATTR2BIG       = 10096,
+
+       /* can be used for internal errors */
+       NFS4ERR_FIRST_FREE
 };
 
 /* error codes for internal client use */