smb3: optimize open to not send query file internal info

We can cut one third of the traffic on open by not querying the
inode number explicitly via SMB3 query_info since it is now
returned on open in the qfid context.

This is better in multiple ways, and
speeds up file open about 10% (more if network is slow).
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/smb2file.c

@@ -88,14 +88,20 @@ smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
 	}
 
 	if (buf) {
-		/* open response does not have IndexNumber field - get it */
-		rc = SMB2_get_srv_num(xid, oparms->tcon, fid->persistent_fid,
+		/* if open response does not have IndexNumber field - get it */
+		if (smb2_data->IndexNumber == 0) {
+			rc = SMB2_get_srv_num(xid, oparms->tcon,
+				      fid->persistent_fid,
 				      fid->volatile_fid,
 				      &smb2_data->IndexNumber);
-		if (rc) {
-			/* let get_inode_info disable server inode numbers */
-			smb2_data->IndexNumber = 0;
-			rc = 0;
+			if (rc) {
+				/*
+				 * let get_inode_info disable server inode
+				 * numbers
+				 */
+				smb2_data->IndexNumber = 0;
+				rc = 0;
+			}
 		}
 		move_smb2_info_to_cifs(buf, smb2_data);
 	}

fs/cifs/smb2ops.c

@@ -754,11 +754,12 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid)
 	tcon->crfid.is_valid = true;
 	kref_init(&tcon->crfid.refcount);
 
+	/* BB TBD check to see if oplock level check can be removed below */
 	if (o_rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE) {
 		kref_get(&tcon->crfid.refcount);
-		oplock = smb2_parse_lease_state(server, o_rsp,
-						&oparms.fid->epoch,
-						oparms.fid->lease_key);
+		smb2_parse_contexts(server, o_rsp,
+				&oparms.fid->epoch,
+				oparms.fid->lease_key, &oplock, NULL);
 	} else
 		goto oshr_exit;
 

fs/cifs/smb2pdu.c

@@ -1873,10 +1873,21 @@ create_reconnect_durable_buf(struct cifs_fid *fid)
 	return buf;
 }
 
-__u8
-smb2_parse_lease_state(struct TCP_Server_Info *server,
+static void
+parse_query_id_ctxt(struct create_context *cc, struct smb2_file_all_info *buf)
+{
+	struct create_on_disk_id *pdisk_id = (struct create_on_disk_id *)cc;
+
+	cifs_dbg(FYI, "parse query id context 0x%llx 0x%llx\n",
+		pdisk_id->DiskFileId, pdisk_id->VolumeId);
+	buf->IndexNumber = pdisk_id->DiskFileId;
+}
+
+void
+smb2_parse_contexts(struct TCP_Server_Info *server,
 		       struct smb2_create_rsp *rsp,
-		       unsigned int *epoch, char *lease_key)
+		       unsigned int *epoch, char *lease_key, __u8 *oplock,
+		       struct smb2_file_all_info *buf)
 {
 	char *data_offset;
 	struct create_context *cc;
@@ -1884,15 +1895,24 @@ smb2_parse_lease_state(struct TCP_Server_Info *server,
 	unsigned int remaining;
 	char *name;
 
+	*oplock = 0;
 	data_offset = (char *)rsp + le32_to_cpu(rsp->CreateContextsOffset);
 	remaining = le32_to_cpu(rsp->CreateContextsLength);
 	cc = (struct create_context *)data_offset;
+
+	/* Initialize inode number to 0 in case no valid data in qfid context */
+	if (buf)
+		buf->IndexNumber = 0;
+
 	while (remaining >= sizeof(struct create_context)) {
 		name = le16_to_cpu(cc->NameOffset) + (char *)cc;
 		if (le16_to_cpu(cc->NameLength) == 4 &&
-		    strncmp(name, "RqLs", 4) == 0)
-			return server->ops->parse_lease_buf(cc, epoch,
-							    lease_key);
+		    strncmp(name, SMB2_CREATE_REQUEST_LEASE, 4) == 0)
+			*oplock = server->ops->parse_lease_buf(cc, epoch,
+							   lease_key);
+		else if (buf && (le16_to_cpu(cc->NameLength) == 4) &&
+		    strncmp(name, SMB2_CREATE_QUERY_ON_DISK_ID, 4) == 0)
+			parse_query_id_ctxt(cc, buf);
 
 		next = le32_to_cpu(cc->Next);
 		if (!next)
@@ -1901,7 +1921,10 @@ smb2_parse_lease_state(struct TCP_Server_Info *server,
 		cc = (struct create_context *)((char *)cc + next);
 	}
 
-	return 0;
+	if (rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE)
+		*oplock = rsp->OplockLevel;
+
+	return;
 }
 
 static int
@@ -2588,12 +2611,9 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 		buf->DeletePending = 0;
 	}
 
-	if (rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE)
-		*oplock = smb2_parse_lease_state(server, rsp,
-						 &oparms->fid->epoch,
-						 oparms->fid->lease_key);
-	else
-		*oplock = rsp->OplockLevel;
+
+	smb2_parse_contexts(server, rsp, &oparms->fid->epoch,
+			    oparms->fid->lease_key, oplock, buf);
 creat_exit:
 	SMB2_open_free(&rqst);
 	free_rsp_buf(resp_buftype, rsp);

fs/cifs/smb2pdu.h

@@ -818,7 +818,9 @@ struct durable_reconnect_context_v2 {
 } __packed;
 
 /* See MS-SMB2 2.2.14.2.9 */
-struct on_disk_id {
+struct create_on_disk_id {
+	struct create_context ccontext;
+	__u8   Name[8];
 	__le64 DiskFileId;
 	__le64 VolumeId;
 	__u32  Reserved[4];

fs/cifs/smb2proto.h

@@ -228,9 +228,10 @@ extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *);
 
 extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *,
 					enum securityEnum);
-extern __u8 smb2_parse_lease_state(struct TCP_Server_Info *server,
-				   struct smb2_create_rsp *rsp,
-				   unsigned int *epoch, char *lease_key);
+extern void smb2_parse_contexts(struct TCP_Server_Info *server,
+				struct smb2_create_rsp *rsp,
+				unsigned int *epoch, char *lease_key,
+				__u8 *oplock, struct smb2_file_all_info *buf);
 extern int smb3_encryption_required(const struct cifs_tcon *tcon);
 extern int smb2_validate_iov(unsigned int offset, unsigned int buffer_length,
 			     struct kvec *iov, unsigned int min_buf_size);