LU-8066 obdclass: don't copy ops structures in to new type.

[fs/lustre-release.git] / lustre / include / lustre_linkea.h

diff --git a/lustre/include/lustre_linkea.h b/lustre/include/lustre_linkea.h
index acb8442..3bf6e2b 100644 (file)
--- 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;
+       }
+}