[PATCH 18/24] nfsd: send basic file attributes in CB_NOTIFY

[Jeff Layton <jlayton@kernel.org>]

In addition to the filename, send attributes about the inode in a
CB_NOTIFY event. This patch just adds a the basic inode information that
can be acquired via GETATTR.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/nfsd/nfs4xdr.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 49ca24851707..0cdce460f9c8 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4104,12 +4104,21 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 	goto out;
 }
 
+#define CB_NOTIFY_STATX_REQUEST_MASK (STATX_BASIC_STATS   | \
+				      STATX_BTIME	  | \
+				      STATX_CHANGE_COOKIE)
+
 static bool
 nfsd4_setup_notify_entry4(struct notify_entry4 *ne, struct xdr_stream *xdr,
 			  struct dentry *dentry, struct nfs4_delegation *dp,
 			  struct nfsd_file *nf, char *name, u32 namelen)
 {
+	struct path path =  { .mnt = nf->nf_file->f_path.mnt,
+			      .dentry = dentry };
+	struct nfsd4_fattr_args args = { };
 	uint32_t *attrmask;
+	__be32 status;
+	int ret;
 
 	/* Reserve space for attrmask */
 	attrmask = xdr_reserve_space(xdr, 3 * sizeof(uint32_t));
@@ -4120,6 +4129,41 @@ nfsd4_setup_notify_entry4(struct notify_entry4 *ne, struct xdr_stream *xdr,
 	ne->ne_file.len = namelen;
 	ne->ne_attrs.attrmask.element = attrmask;
 
+	/* FIXME: d_find_alias for inode ? */
+	if (!path.dentry || !d_inode(path.dentry))
+		goto noattrs;
+
+	/*
+	 * It is possible that the client was granted a delegation when a file
+	 * was created. Note that we don't issue a CB_GETATTR here since stale
+	 * attributes are presumably ok.
+	 */
+	ret = vfs_getattr(&path, &args.stat, CB_NOTIFY_STATX_REQUEST_MASK, AT_STATX_SYNC_AS_STAT);
+	if (ret)
+		goto noattrs;
+
+	args.change_attr = nfsd4_change_attribute(&args.stat);
+
+	attrmask[0] = FATTR4_WORD0_TYPE | FATTR4_WORD0_CHANGE |
+		      FATTR4_WORD0_SIZE | FATTR4_WORD0_FILEID;
+	attrmask[1] = FATTR4_WORD1_MODE | FATTR4_WORD1_NUMLINKS | FATTR4_WORD1_RAWDEV |
+		      FATTR4_WORD1_SPACE_USED | FATTR4_WORD1_TIME_ACCESS |
+		      FATTR4_WORD1_TIME_METADATA | FATTR4_WORD1_TIME_MODIFY;
+	attrmask[2] = 0;
+
+	if (args.stat.result_mask & STATX_BTIME)
+		attrmask[1] |= FATTR4_WORD1_TIME_CREATE;
+
+	ne->ne_attrs.attrmask.count = 2;
+	ne->ne_attrs.attr_vals.data = (u8 *)xdr->p;
+
+	status = nfsd4_encode_attr_vals(xdr, attrmask, &args);
+	if (status != nfs_ok)
+		goto noattrs;
+
+	ne->ne_attrs.attr_vals.len = (u8 *)xdr->p - ne->ne_attrs.attr_vals.data;
+	return true;
+noattrs:
 	attrmask[0] = 0;
 	attrmask[1] = 0;
 	attrmask[2] = 0;

-- 
2.53.0