[PATCH 2/2] nfsd: implement chage_attr_type attribute

[Christoph Hellwig <hch@lst.de>]

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/nfsd/nfs4xdr.c    | 16 ++++++++++++++++
 fs/nfsd/nfsd.h       |  2 +-
 include/linux/nfs4.h |  9 +++++++++
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index eeea7a9..3205b55 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1730,6 +1730,15 @@ static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
 	return p;
 }
 
+static __be32 *encode_change_attr_type(__be32 *p, struct inode *inode)
+{
+	if (IS_I_VERSION(inode))
+		*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_VERSION_COUNTER);
+	else
+		*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
+	return p;
+}
+
 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
 {
 	*p++ = cpu_to_be32(c->atomic);
@@ -2535,6 +2544,13 @@ out_acl:
 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
 	}
 
+	if (bmval2 & FATTR4_WORD2_CHANGE_ATTR_TYPE) {
+		p = xdr_reserve_space(xdr, 4);
+		if (!p)
+			goto out_resource;
+		p = encode_change_attr_type(p, dentry->d_inode);
+	}
+
 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
 	status = nfs_ok;
diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 43b6a36..59a734f 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -342,7 +342,7 @@ void		nfsd_lockd_shutdown(void);
 
 #define NFSD4_2_SUPPORTED_ATTRS_WORD2 \
 	(NFSD4_1_SUPPORTED_ATTRS_WORD2 | \
-	NFSD4_2_SECURITY_ATTRS)
+	FATTR4_WORD2_CHANGE_ATTR_TYPE | NFSD4_2_SECURITY_ATTRS)
 
 static inline u32 nfsd_suppattrs0(u32 minorversion)
 {
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 356acc2..85ccd06 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -413,6 +413,7 @@ enum lock_type4 {
 #define FATTR4_WORD1_FS_LAYOUT_TYPES    (1UL << 30)
 #define FATTR4_WORD2_LAYOUT_BLKSIZE     (1UL << 1)
 #define FATTR4_WORD2_MDSTHRESHOLD       (1UL << 4)
+#define FATTR4_WORD2_CHANGE_ATTR_TYPE   (1UL << 15)
 #define FATTR4_WORD2_SECURITY_LABEL     (1UL << 16)
 
 /* MDS threshold bitmap bits */
@@ -558,4 +559,12 @@ enum data_content4 {
 	NFS4_CONTENT_HOLE		= 1,
 };
 
+enum change_attr_type4 {
+	NFS4_CHANGE_TYPE_IS_MONOTONIC_INCR	= 0,
+	NFS4_CHANGE_TYPE_IS_VERSION_COUNTER	= 1,
+	NFS4_CHANGE_TYPE_IS_VERSION_COUNTER_NOPNFS = 2,
+	NFS4_CHANGE_TYPE_IS_TIME_METADATA	= 3,
+	NFS4_CHANGE_TYPE_IS_UNDEFINED		= 4
+};
+
 #endif
-- 
1.9.1