[PATCH v3 6/7] NFSv4: Add O_DENY* open flags support

[Pavel Shilovsky]

by passing these flags to NFSv4 open request.

Signed-off-by: Pavel Shilovsky 
---
 fs/nfs/nfs4xdr.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 26b1439..58ddc74 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1325,7 +1325,8 @@ static void encode_lookup(struct xdr_stream *xdr, const struct qstr *name, struc
    encode_string(xdr, name->len, name->name);
 }

-static void encode_share_access(struct xdr_stream *xdr, fmode_t fmode)
+static void encode_share_access(struct xdr_stream *xdr, fmode_t fmode,
+				int open_flags)
 {
    __be32 *p;

@@ -1343,7 +1344,22 @@ static void encode_share_access(struct xdr_stream *xdr, fmode_t fmode)
    default:
    	*p++ = cpu_to_be32(0);
    }
-	*p = cpu_to_be32(0);		/* for linux, share_deny = 0 always */
+	if (open_flags & O_DENYMAND) {
+		switch (open_flags & (O_DENYREAD|O_DENYWRITE)) {
+		case O_DENYREAD:
+			*p = cpu_to_be32(NFS4_SHARE_DENY_READ);
+			break;
+		case O_DENYWRITE:
+			*p = cpu_to_be32(NFS4_SHARE_DENY_WRITE);
+			break;
+		case O_DENYREAD|O_DENYWRITE:
+			*p = cpu_to_be32(NFS4_SHARE_DENY_BOTH);
+			break;
+		default:
+			*p = cpu_to_be32(0);
+		}
+	} else
+		*p = cpu_to_be32(0);
 }

static inline void encode_openhdr(struct xdr_stream *xdr, const struct nfs_openargs *arg)
@@ -1354,7 +1370,7 @@ static inline void encode_openhdr(struct xdr_stream *xdr, const struct nfs_opena
  * owner 4 = 32
  */
    encode_nfs4_seqid(xdr, arg->seqid);
-	encode_share_access(xdr, arg->fmode);
+	encode_share_access(xdr, arg->fmode, arg->open_flags);
    p = reserve_space(xdr, 36);
    p = xdr_encode_hyper(p, arg->clientid);
    *p++ = cpu_to_be32(24);
@@ -1491,7 +1507,7 @@ static void encode_open_downgrade(struct xdr_stream *xdr, const struct nfs_close
    encode_op_hdr(xdr, OP_OPEN_DOWNGRADE, decode_open_downgrade_maxsz, hdr);
    encode_nfs4_stateid(xdr, arg->stateid);
    encode_nfs4_seqid(xdr, arg->seqid);
-	encode_share_access(xdr, arg->fmode);
+	encode_share_access(xdr, arg->fmode, 0);
 }

static void