X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Finclude%2Flustre_linkea.h;h=3bf6e2b54fd9b4e86602c93521d327f3faa38253;hb=acd639bf0de0c39419dff94fd6d338283a1ddb24;hp=acb8442930a9725ba90ca58d98b97e54f50c842c;hpb=2f41b688058532248e69ff0194c27616f4dfb6d5;p=fs%2Flustre-release.git

diff --git a/lustre/include/lustre_linkea.h b/lustre/include/lustre_linkea.h
index acb8442..3bf6e2b 100644
--- a/lustre/include/lustre_linkea.h
+++ b/lustre/include/lustre_linkea.h
@@ -21,13 +21,24 @@
  * GPL HEADER END
  */
 /*
- * Copyright (c) 2013, Intel Corporation.
+ * Copyright (c) 2013, 2017, Intel Corporation.
  * Use is subject to license terms.
  *
  * Author: di wang <di.wang@intel.com>
  */
 
-#define DEFAULT_LINKEA_SIZE	4096
+/* There are several reasons to restrict the linkEA size:
+ *
+ * 1. Under DNE mode, if we do not restrict the linkEA size, and if there
+ *    are too many cross-MDTs hard links to the same object, then it will
+ *    casue the llog overflow.
+ *
+ * 2. Some backend has limited size for EA. For example, if without large
+ *    EA enabled, the ldiskfs will make all EAs to share one (4K) EA block.
+ *
+ * 3. Too many entries in linkEA will seriously affect linkEA performance
+ *    because we only support to locate linkEA entry consecutively. */
+#define MAX_LINKEA_SIZE	4096
 
 struct linkea_data {
 	/**
@@ -44,16 +55,41 @@ struct linkea_data {
 
 int linkea_data_new(struct linkea_data *ldata, struct lu_buf *buf);
 int linkea_init(struct linkea_data *ldata);
+int linkea_init_with_rec(struct linkea_data *ldata);
 void linkea_entry_unpack(const struct link_ea_entry *lee, int *reclen,
 			 struct lu_name *lname, struct lu_fid *pfid);
+int linkea_entry_pack(struct link_ea_entry *lee, const struct lu_name *lname,
+		      const struct lu_fid *pfid);
 int linkea_add_buf(struct linkea_data *ldata, const struct lu_name *lname,
 		   const struct lu_fid *pfid);
 void linkea_del_buf(struct linkea_data *ldata, const struct lu_name *lname);
+int linkea_links_new(struct linkea_data *ldata, struct lu_buf *buf,
+		     const struct lu_name *cname, const struct lu_fid *pfid);
+int linkea_overflow_shrink(struct linkea_data *ldata);
 int linkea_links_find(struct linkea_data *ldata, const struct lu_name *lname,
 		      const struct lu_fid  *pfid);
 
-#define LINKEA_NEXT_ENTRY(ldata)	\
-	(struct link_ea_entry *)((char *)ldata.ld_lee + ldata.ld_reclen)
+static inline void linkea_first_entry(struct linkea_data *ldata)
+{
+	LASSERT(ldata != NULL);
+	LASSERT(ldata->ld_leh != NULL);
+
+	if (ldata->ld_leh->leh_reccount == 0)
+		ldata->ld_lee = NULL;
+	else
+		ldata->ld_lee = (struct link_ea_entry *)(ldata->ld_leh + 1);
+}
+
+static inline void linkea_next_entry(struct linkea_data *ldata)
+{
+	LASSERT(ldata != NULL);
+	LASSERT(ldata->ld_leh != NULL);
 
-#define LINKEA_FIRST_ENTRY(ldata)	\
-	(struct link_ea_entry *)(ldata.ld_leh + 1)
+	if (ldata->ld_lee != NULL) {
+		ldata->ld_lee = (struct link_ea_entry *)((char *)ldata->ld_lee +
+							 ldata->ld_reclen);
+		if ((char *)ldata->ld_lee >= ((char *)ldata->ld_leh +
+					      ldata->ld_leh->leh_len))
+			ldata->ld_lee = NULL;
+	}
+}