nfs: get clone_blksize when probing fsinfo

NFSv42 CLONE operation is supposed to respect it.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 868472b6b303..9f656791a338 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -4764,6 +4764,28 @@ static int decode_attr_layout_blksize(struct xdr_stream *xdr, uint32_t *bitmap,
         return 0;
 }
 
+/*
+ * The granularity of a CLONE operation.
+ */
+static int decode_attr_clone_blksize(struct xdr_stream *xdr, uint32_t *bitmap,
+                                     uint32_t *res)
+{
+        __be32 *p;
+
+        dprintk("%s: bitmap is %x\n", __func__, bitmap[2]);
+        *res = 0;
+        if (bitmap[2] & FATTR4_WORD2_CLONE_BLKSIZE) {
+                p = xdr_inline_decode(xdr, 4);
+                if (unlikely(!p)) {
+                        print_overflow_msg(__func__, xdr);
+                        return -EIO;
+                }
+                *res = be32_to_cpup(p);
+                bitmap[2] &= ~FATTR4_WORD2_CLONE_BLKSIZE;
+        }
+        return 0;
+}
+
 static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
 {
         unsigned int savep;
@@ -4798,6 +4820,9 @@ static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
         status = decode_attr_layout_blksize(xdr, bitmap, &fsinfo->blksize);
         if (status)
                 goto xdr_error;
+        status = decode_attr_clone_blksize(xdr, bitmap, &fsinfo->clone_blksize);
+        if (status)
+                goto xdr_error;
 
         status = verify_attr_len(xdr, savep, attrlen);
 xdr_error: