X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fobdclass%2Fllog_cat.c;h=27b9aad07b9622710c6788fd0634bf727980ef95;hp=ae443e64e62793fd6ada7e6206eae4a71e5142c3;hb=HEAD;hpb=0f22e4c098b1f7885ef509bbfc346b3e8905b28d

diff --git a/lustre/obdclass/llog_cat.c b/lustre/obdclass/llog_cat.c
index ae443e6..3d9cceb 100644
--- a/lustre/obdclass/llog_cat.c
+++ b/lustre/obdclass/llog_cat.c
@@ -15,11 +15,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
@@ -27,11 +23,10 @@
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2012, 2017, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
- * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * lustre/obdclass/llog_cat.c
  *
@@ -53,6 +48,15 @@
 
 #include "llog_internal.h"
 
+
+/**
+ * lockdep markers for nested struct llog_handle::lgh_lock locking.
+ */
+enum {
+	LLOGH_CAT,
+	LLOGH_LOG,
+};
+
 /* Create a new log handle and add it to the open list.
  * This log handle will be closed when all of the records in it are removed.
  *
@@ -65,28 +69,101 @@ static int llog_cat_new_log(const struct lu_env *env,
 {
 	struct llog_thread_info	*lgi = llog_info(env);
 	struct llog_logid_rec	*rec = &lgi->lgi_logid;
-	int			 rc;
+	struct thandle *handle = NULL;
+	struct dt_device *dt = NULL;
+	struct llog_log_hdr	*llh = cathandle->lgh_hdr;
+	int			 rc, index;
 
 	ENTRY;
 
-	if (OBD_FAIL_CHECK(OBD_FAIL_MDS_LLOG_CREATE_FAILED))
+	index = (cathandle->lgh_last_idx + 1) % (llog_max_idx(llh) + 1);
+
+	/* check that new llog index will not overlap with the first one.
+	 * - llh_cat_idx is the index just before the first/oldest still in-use
+	 *	index in catalog
+	 * - lgh_last_idx is the last/newest used index in catalog
+	 *
+	 * When catalog is not wrapped yet then lgh_last_idx is always larger
+	 * than llh_cat_idx. After the wrap around lgh_last_idx re-starts
+	 * from 0 and llh_cat_idx becomes the upper limit for it
+	 *
+	 * Check if catalog has already wrapped around or not by comparing
+	 * last_idx and cat_idx */
+	if ((index == llh->llh_cat_idx + 1 && llh->llh_count > 1) ||
+	    (index == 0 && llh->llh_cat_idx == 0)) {
+		if (cathandle->lgh_name == NULL) {
+			CWARN("%s: there are no more free slots in catalog "DFID"\n",
+			      loghandle2name(loghandle),
+			      PLOGID(&cathandle->lgh_id));
+		} else {
+			CWARN("%s: there are no more free slots in catalog %s\n",
+			      loghandle2name(loghandle), cathandle->lgh_name);
+		}
+		RETURN(-ENOSPC);
+	}
+
+	if (CFS_FAIL_CHECK(OBD_FAIL_MDS_LLOG_CREATE_FAILED))
 		RETURN(-ENOSPC);
 
+	if (loghandle->lgh_hdr != NULL) {
+		/* If llog object is remote and creation is failed, lgh_hdr
+		 * might be left over here, free it first */
+		LASSERT(!llog_exist(loghandle));
+		OBD_FREE_LARGE(loghandle->lgh_hdr, loghandle->lgh_hdr_size);
+		loghandle->lgh_hdr = NULL;
+	}
+
+	if (th == NULL) {
+		dt = lu2dt_dev(cathandle->lgh_obj->do_lu.lo_dev);
+
+		handle = dt_trans_create(env, dt);
+		if (IS_ERR(handle))
+			RETURN(PTR_ERR(handle));
+
+		/* Create update llog object synchronously, which
+		 * happens during inialization process see
+		 * lod_sub_prep_llog(), to make sure the update
+		 * llog object is created before corss-MDT writing
+		 * updates into the llog object */
+		if (cathandle->lgh_ctxt->loc_flags & LLOG_CTXT_FLAG_NORMAL_FID)
+			handle->th_sync = 1;
+
+		handle->th_wait_submit = 1;
+
+		rc = llog_declare_create(env, loghandle, handle);
+		if (rc != 0)
+			GOTO(out, rc);
+
+		rec->lid_hdr.lrh_len = sizeof(*rec);
+		rec->lid_hdr.lrh_type = LLOG_LOGID_MAGIC;
+		rec->lid_id = loghandle->lgh_id;
+		rc = llog_declare_write_rec(env, cathandle, &rec->lid_hdr, -1,
+					    handle);
+		if (rc != 0)
+			GOTO(out, rc);
+
+		rc = dt_trans_start_local(env, dt, handle);
+		if (rc != 0)
+			GOTO(out, rc);
+
+		th = handle;
+	}
+
 	rc = llog_create(env, loghandle, th);
 	/* if llog is already created, no need to initialize it */
 	if (rc == -EEXIST) {
-		RETURN(0);
+		GOTO(out, rc = 0);
 	} else if (rc != 0) {
 		CERROR("%s: can't create new plain llog in catalog: rc = %d\n",
-		       loghandle->lgh_ctxt->loc_obd->obd_name, rc);
-		RETURN(rc);
+		       loghandle2name(loghandle), rc);
+		GOTO(out, rc);
 	}
 
 	rc = llog_init_handle(env, loghandle,
 			      LLOG_F_IS_PLAIN | LLOG_F_ZAP_WHEN_EMPTY,
 			      &cathandle->lgh_hdr->llh_tgtuuid);
-	if (rc)
-		GOTO(out_destroy, rc);
+	if (rc < 0)
+		GOTO(out, rc);
 
 	/* build the record for this log in the catalog */
 	rec->lid_hdr.lrh_len = sizeof(*rec);
@@ -100,18 +177,184 @@ static int llog_cat_new_log(const struct lu_env *env,
 	if (rc < 0)
 		GOTO(out_destroy, rc);
 
-	CDEBUG(D_OTHER, "new recovery log "DOSTID":%x for index %u of catalog"
-	       DOSTID"\n", POSTID(&loghandle->lgh_id.lgl_oi),
-	       loghandle->lgh_id.lgl_ogen, rec->lid_hdr.lrh_index,
-	       POSTID(&cathandle->lgh_id.lgl_oi));
+	CDEBUG(D_OTHER, "new plain log "DFID".%u of catalog "DFID"\n",
+	       PLOGID(&loghandle->lgh_id), rec->lid_hdr.lrh_index,
+	       PLOGID(&cathandle->lgh_id));
 
 	loghandle->lgh_hdr->llh_cat_idx = rec->lid_hdr.lrh_index;
-	RETURN(0);
+
+	/* limit max size of plain llog so that space can be
+	 * released sooner, especially on small filesystems */
+	/* 2MB for the cases when free space hasn't been learned yet */
+	loghandle->lgh_max_size = 2 << 20;
+	dt = lu2dt_dev(cathandle->lgh_obj->do_lu.lo_dev);
+	rc = dt_statfs(env, dt, &lgi->lgi_statfs);
+	if (rc == 0 && lgi->lgi_statfs.os_bfree > 0) {
+		__u64 freespace = (lgi->lgi_statfs.os_bfree *
+				  lgi->lgi_statfs.os_bsize) >> 6;
+		if (freespace < loghandle->lgh_max_size)
+			loghandle->lgh_max_size = freespace;
+		/* shouldn't be > 128MB in any case?
+		 * it's 256K records of 512 bytes each */
+		if (freespace > (128 << 20))
+			loghandle->lgh_max_size = 128 << 20;
+	}
+	if (unlikely(CFS_FAIL_PRECHECK(OBD_FAIL_PLAIN_RECORDS) ||
+		     CFS_FAIL_PRECHECK(OBD_FAIL_CATALOG_FULL_CHECK))) {
+		// limit the numer of plain records for test
+		loghandle->lgh_max_size = loghandle->lgh_hdr_size +
+		       cfs_fail_val * 64;
+	}
+
+	rc = 0;
+
+out:
+	if (handle != NULL) {
+		handle->th_result = rc >= 0 ? 0 : rc;
+		dt_trans_stop(env, dt, handle);
+	}
+	RETURN(rc);
+
 out_destroy:
-	llog_destroy(env, loghandle);
+	/* to signal llog_cat_close() it shouldn't try to destroy the llog,
+	 * we want to destroy it in this transaction, otherwise the object
+	 * becomes an orphan */
+	loghandle->lgh_hdr->llh_flags &= ~LLOG_F_ZAP_WHEN_EMPTY;
+	/* this is to mimic full log, so another llog_cat_current_log()
+	 * can skip it and ask for another onet */
+	loghandle->lgh_last_idx = llog_max_idx(loghandle->lgh_hdr) + 1;
+	llog_trans_destroy(env, loghandle, th);
+	if (handle != NULL)
+		dt_trans_stop(env, dt, handle);
 	RETURN(rc);
 }
 
+static int llog_cat_refresh(const struct lu_env *env,
+			    struct llog_handle *cathandle)
+{
+	struct llog_handle *loghandle;
+	int rc;
+
+	down_write(&cathandle->lgh_lock);
+	list_for_each_entry(loghandle, &cathandle->u.chd.chd_head,
+			    u.phd.phd_entry) {
+		if (!llog_exist(loghandle))
+			continue;
+
+		down_write(&loghandle->lgh_lock);
+		rc = llog_read_header(env, loghandle, NULL);
+		up_write(&loghandle->lgh_lock);
+		if (rc)
+			goto unlock;
+	}
+
+	rc = llog_read_header(env, cathandle, NULL);
+unlock:
+	up_write(&cathandle->lgh_lock);
+
+	return rc;
+}
+
+/*
+ * prepare current/next log for catalog.
+ *
+ * if \a *ploghandle is NULL, open it, and declare create, NB, if \a
+ * *ploghandle is remote, create it synchronously here, see comments
+ * below.
+ *
+ * \a cathandle->lgh_lock is down_read-ed, it gets down_write-ed if \a
+ * *ploghandle has to be opened.
+ */
+static int llog_cat_prep_log(const struct lu_env *env,
+			     struct llog_handle *cathandle,
+			     struct llog_handle **ploghandle,
+			     struct thandle *th)
+{
+	int rc;
+	int sem_upgraded;
+
+start:
+	rc = 0;
+	sem_upgraded = 0;
+	if (IS_ERR_OR_NULL(*ploghandle)) {
+		up_read(&cathandle->lgh_lock);
+		down_write(&cathandle->lgh_lock);
+		sem_upgraded = 1;
+		if (IS_ERR_OR_NULL(*ploghandle)) {
+			struct llog_handle *loghandle;
+
+			rc = llog_open(env, cathandle->lgh_ctxt, &loghandle,
+				       NULL, NULL, LLOG_OPEN_NEW);
+			if (!rc) {
+				*ploghandle = loghandle;
+				list_add_tail(&loghandle->u.phd.phd_entry,
+					      &cathandle->u.chd.chd_head);
+			}
+		}
+		if (rc)
+			GOTO(out, rc);
+	}
+
+	rc = llog_exist(*ploghandle);
+	if (rc < 0)
+		GOTO(out, rc);
+	if (rc)
+		GOTO(out, rc = 0);
+
+	if (dt_object_remote(cathandle->lgh_obj)) {
+		down_write_nested(&(*ploghandle)->lgh_lock, LLOGH_LOG);
+		if (!llog_exist(*ploghandle)) {
+			/* For remote operation, if we put the llog object
+			 * creation in the current transaction, then the
+			 * llog object will not be created on the remote
+			 * target until the transaction stop, if other
+			 * operations start before the transaction stop,
+			 * and use the same llog object, will be dependent
+			 * on the success of this transaction. So let's
+			 * create the llog object synchronously here to
+			 * remove the dependency. */
+			rc = llog_cat_new_log(env, cathandle, *ploghandle,
+					      NULL);
+			if (rc == -ESTALE) {
+				up_write(&(*ploghandle)->lgh_lock);
+				if (sem_upgraded)
+					up_write(&cathandle->lgh_lock);
+				else
+					up_read(&cathandle->lgh_lock);
+
+				rc = llog_cat_refresh(env, cathandle);
+				down_read_nested(&cathandle->lgh_lock,
+						 LLOGH_CAT);
+				if (rc)
+					return rc;
+				/* *ploghandle might become NULL, restart */
+				goto start;
+			}
+		}
+		up_write(&(*ploghandle)->lgh_lock);
+	} else {
+		struct llog_thread_info	*lgi = llog_info(env);
+		struct llog_logid_rec *lirec = &lgi->lgi_logid;
+
+		rc = llog_declare_create(env, *ploghandle, th);
+		if (rc)
+			GOTO(out, rc);
+
+		lirec->lid_hdr.lrh_len = sizeof(*lirec);
+		rc = llog_declare_write_rec(env, cathandle, &lirec->lid_hdr, -1,
+					    th);
+	}
+
+out:
+	if (sem_upgraded) {
+		up_write(&cathandle->lgh_lock);
+		down_read_nested(&cathandle->lgh_lock, LLOGH_CAT);
+		if (rc == 0)
+			goto start;
+	}
+	return rc;
+}
+
 /* Open an existent log handle and add it to the open list.
  * This log handle will be closed when all of the records in it are removed.
  *
@@ -141,16 +384,16 @@ int llog_cat_id2handle(const struct lu_env *env, struct llog_handle *cathandle,
 
 		if (ostid_id(&cgl->lgl_oi) == ostid_id(&logid->lgl_oi) &&
 		    ostid_seq(&cgl->lgl_oi) == ostid_seq(&logid->lgl_oi)) {
-			if (cgl->lgl_ogen != logid->lgl_ogen) {
-				CERROR("%s: log "DOSTID" generation %x != %x\n",
-				       loghandle->lgh_ctxt->loc_obd->obd_name,
-				       POSTID(&logid->lgl_oi), cgl->lgl_ogen,
-				       logid->lgl_ogen);
+			*res = llog_handle_get(loghandle);
+			if (!*res) {
+				CERROR("%s: log "DFID" refcount is zero!\n",
+				       loghandle2name(loghandle),
+				       PLOGID(logid));
 				continue;
 			}
 			loghandle->u.phd.phd_cat_handle = cathandle;
 			up_write(&cathandle->lgh_lock);
-			GOTO(out, rc = 0);
+			RETURN(rc);
 		}
 	}
 	up_write(&cathandle->lgh_lock);
@@ -158,19 +401,21 @@ int llog_cat_id2handle(const struct lu_env *env, struct llog_handle *cathandle,
 	rc = llog_open(env, cathandle->lgh_ctxt, &loghandle, logid, NULL,
 		       LLOG_OPEN_EXISTS);
 	if (rc < 0) {
-		CERROR("%s: error opening log id "DOSTID":%x: rc = %d\n",
-		       cathandle->lgh_ctxt->loc_obd->obd_name,
-		       POSTID(&logid->lgl_oi), logid->lgl_ogen, rc);
+		CERROR("%s: error opening log id "DFID": rc = %d\n",
+		       loghandle2name(cathandle), PLOGID(logid), rc);
 		RETURN(rc);
 	}
 
-	rc = llog_init_handle(env, loghandle, LLOG_F_IS_PLAIN | fmt, NULL);
+	rc = llog_init_handle(env, loghandle, LLOG_F_IS_PLAIN |
+			      LLOG_F_ZAP_WHEN_EMPTY | fmt, NULL);
 	if (rc < 0) {
 		llog_close(env, loghandle);
-		loghandle = NULL;
+		*res = NULL;
 		RETURN(rc);
 	}
 
+	*res = llog_handle_get(loghandle);
+	LASSERT(*res);
 	down_write(&cathandle->lgh_lock);
 	list_add_tail(&loghandle->u.phd.phd_entry, &cathandle->u.chd.chd_head);
 	up_write(&cathandle->lgh_lock);
@@ -179,11 +424,7 @@ int llog_cat_id2handle(const struct lu_env *env, struct llog_handle *cathandle,
 	loghandle->u.phd.phd_cookie.lgc_lgl = cathandle->lgh_id;
 	loghandle->u.phd.phd_cookie.lgc_index =
 				loghandle->lgh_hdr->llh_cat_idx;
-	EXIT;
-out:
-	llog_handle_get(loghandle);
-	*res = loghandle;
-	return 0;
+	RETURN(0);
 }
 
 int llog_cat_close(const struct lu_env *env, struct llog_handle *cathandle)
@@ -208,8 +449,7 @@ int llog_cat_close(const struct lu_env *env, struct llog_handle *cathandle)
 			if (rc)
 				CERROR("%s: failure destroying log during "
 				       "cleanup: rc = %d\n",
-				       loghandle->lgh_ctxt->loc_obd->obd_name,
-				       rc);
+				       loghandle2name(loghandle), rc);
 
 			index = loghandle->u.phd.phd_cookie.lgc_index;
 			llog_cat_cleanup(env, cathandle, NULL, index);
@@ -224,14 +464,6 @@ int llog_cat_close(const struct lu_env *env, struct llog_handle *cathandle)
 }
 EXPORT_SYMBOL(llog_cat_close);
 
-/**
- * lockdep markers for nested struct llog_handle::lgh_lock locking.
- */
-enum {
-        LLOGH_CAT,
-        LLOGH_LOG
-};
-
 /** Return the currently active log handle.  If the current log handle doesn't
  * have enough space left for the current record, start a new one.
  *
@@ -248,6 +480,12 @@ static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
         struct llog_handle *loghandle = NULL;
         ENTRY;
 
+
+	if (CFS_FAIL_CHECK(OBD_FAIL_MDS_LLOG_CREATE_FAILED2)) {
+		down_write_nested(&cathandle->lgh_lock, LLOGH_CAT);
+		GOTO(next, loghandle);
+	}
+
 	down_read_nested(&cathandle->lgh_lock, LLOGH_CAT);
         loghandle = cathandle->u.chd.chd_current_log;
         if (loghandle) {
@@ -255,8 +493,7 @@ static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
 
 		down_write_nested(&loghandle->lgh_lock, LLOGH_LOG);
 		llh = loghandle->lgh_hdr;
-		if (llh == NULL ||
-		    loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
+		if (llh == NULL || !llog_is_full(loghandle)) {
 			up_read(&cathandle->lgh_lock);
                         RETURN(loghandle);
                 } else {
@@ -275,14 +512,31 @@ static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
 
 		down_write_nested(&loghandle->lgh_lock, LLOGH_LOG);
 		llh = loghandle->lgh_hdr;
-		LASSERT(llh);
-                if (loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
-			up_write(&cathandle->lgh_lock);
-                        RETURN(loghandle);
-                } else {
+		if (llh == NULL || !llog_is_full(loghandle))
+			GOTO(out_unlock, loghandle);
+		else
 			up_write(&loghandle->lgh_lock);
-                }
-        }
+	}
+
+next:
+	/* Sigh, the chd_next_log and chd_current_log is initialized
+	 * in declare phase, and we do not serialize the catlog
+	 * accessing, so it might be possible the llog creation
+	 * thread (see llog_cat_declare_add_rec()) did not create
+	 * llog successfully, then the following thread might
+	 * meet this situation. */
+	if (IS_ERR_OR_NULL(cathandle->u.chd.chd_next_log)) {
+		CERROR("%s: next log does not exist!\n",
+		       loghandle2name(cathandle));
+		loghandle = ERR_PTR(-EIO);
+		if (cathandle->u.chd.chd_next_log == NULL) {
+			/* Store the error in chd_next_log, so
+			 * the following process can get correct
+			 * failure value */
+			cathandle->u.chd.chd_next_log = loghandle;
+		}
+		GOTO(out_unlock, loghandle);
+	}
 
 	CDEBUG(D_INODE, "use next log\n");
 
@@ -290,6 +544,8 @@ static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
 	cathandle->u.chd.chd_current_log = loghandle;
 	cathandle->u.chd.chd_next_log = NULL;
 	down_write_nested(&loghandle->lgh_lock, LLOGH_LOG);
+
+out_unlock:
 	up_write(&cathandle->lgh_lock);
 	LASSERT(loghandle);
 	RETURN(loghandle);
@@ -305,45 +561,50 @@ int llog_cat_add_rec(const struct lu_env *env, struct llog_handle *cathandle,
 		     struct thandle *th)
 {
         struct llog_handle *loghandle;
-        int rc;
-        ENTRY;
+	int rc, retried = 0;
+	ENTRY;
+
+	LASSERT(rec->lrh_len <= cathandle->lgh_ctxt->loc_chunk_size);
 
-        LASSERT(rec->lrh_len <= LLOG_CHUNK_SIZE);
+retry:
 	loghandle = llog_cat_current_log(cathandle, th);
-	LASSERT(!IS_ERR(loghandle));
+	if (IS_ERR(loghandle))
+		RETURN(PTR_ERR(loghandle));
 
 	/* loghandle is already locked by llog_cat_current_log() for us */
 	if (!llog_exist(loghandle)) {
 		rc = llog_cat_new_log(env, cathandle, loghandle, th);
 		if (rc < 0) {
 			up_write(&loghandle->lgh_lock);
+			/* nobody should be trying to use this llog */
+			down_write(&cathandle->lgh_lock);
+			if (cathandle->u.chd.chd_current_log == loghandle)
+				cathandle->u.chd.chd_current_log = NULL;
+			up_write(&cathandle->lgh_lock);
 			RETURN(rc);
 		}
 	}
 	/* now let's try to add the record */
 	rc = llog_write_rec(env, loghandle, rec, reccookie, LLOG_NEXT_IDX, th);
-	if (rc < 0)
+	if (rc < 0) {
 		CDEBUG_LIMIT(rc == -ENOSPC ? D_HA : D_ERROR,
 			     "llog_write_rec %d: lh=%p\n", rc, loghandle);
+		/* -ENOSPC is returned if no empty records left
+		 * and when it's lack of space on the stogage.
+		 * there is no point to try again if it's the second
+		 * case. many callers (like llog test) expect ENOSPC,
+		 * so we preserve this error code, but look for the
+		 * actual cause here */
+		if (rc == -ENOSPC && llog_is_full(loghandle))
+			rc = -ENOBUFS;
+	}
 	up_write(&loghandle->lgh_lock);
-        if (rc == -ENOSPC) {
-		/* try to use next log */
-		loghandle = llog_cat_current_log(cathandle, th);
-		LASSERT(!IS_ERR(loghandle));
-		/* new llog can be created concurrently */
-		if (!llog_exist(loghandle)) {
-			rc = llog_cat_new_log(env, cathandle, loghandle, th);
-			if (rc < 0) {
-				up_write(&loghandle->lgh_lock);
-				RETURN(rc);
-			}
-		}
-		/* now let's try to add the record */
-		rc = llog_write_rec(env, loghandle, rec, reccookie,
-				    LLOG_NEXT_IDX, th);
-		if (rc < 0)
-			CERROR("llog_write_rec %d: lh=%p\n", rc, loghandle);
-		up_write(&loghandle->lgh_lock);
+
+	if (rc == -ENOBUFS) {
+		if (retried++ == 0)
+			GOTO(retry, rc);
+		CERROR("%s: error on 2nd llog: rc = %d\n",
+		       loghandle2name(cathandle), rc);
 	}
 
 	RETURN(rc);
@@ -354,72 +615,43 @@ int llog_cat_declare_add_rec(const struct lu_env *env,
 			     struct llog_handle *cathandle,
 			     struct llog_rec_hdr *rec, struct thandle *th)
 {
-	struct llog_thread_info	*lgi = llog_info(env);
-	struct llog_logid_rec	*lirec = &lgi->lgi_logid;
-	struct llog_handle	*loghandle, *next;
-	int			 rc = 0;
+	int rc;
 
 	ENTRY;
 
-	if (cathandle->u.chd.chd_current_log == NULL) {
-		/* declare new plain llog */
-		down_write(&cathandle->lgh_lock);
-		if (cathandle->u.chd.chd_current_log == NULL) {
-			rc = llog_open(env, cathandle->lgh_ctxt, &loghandle,
-				       NULL, NULL, LLOG_OPEN_NEW);
-			if (rc == 0) {
-				cathandle->u.chd.chd_current_log = loghandle;
-				list_add_tail(&loghandle->u.phd.phd_entry,
-					      &cathandle->u.chd.chd_head);
-			}
-		}
-		up_write(&cathandle->lgh_lock);
-	} else if (cathandle->u.chd.chd_next_log == NULL) {
-		/* declare next plain llog */
-		down_write(&cathandle->lgh_lock);
-		if (cathandle->u.chd.chd_next_log == NULL) {
-			rc = llog_open(env, cathandle->lgh_ctxt, &loghandle,
-				       NULL, NULL, LLOG_OPEN_NEW);
-			if (rc == 0) {
-				cathandle->u.chd.chd_next_log = loghandle;
-				list_add_tail(&loghandle->u.phd.phd_entry,
-					      &cathandle->u.chd.chd_head);
-			}
-		}
-		up_write(&cathandle->lgh_lock);
-	}
+start:
+	down_read_nested(&cathandle->lgh_lock, LLOGH_CAT);
+	rc = llog_cat_prep_log(env, cathandle,
+			       &cathandle->u.chd.chd_current_log, th);
 	if (rc)
-		GOTO(out, rc);
+		GOTO(unlock, rc);
 
-	lirec->lid_hdr.lrh_len = sizeof(*lirec);
+	rc = llog_cat_prep_log(env, cathandle, &cathandle->u.chd.chd_next_log,
+			       th);
+	if (rc)
+		GOTO(unlock, rc);
 
-	if (!llog_exist(cathandle->u.chd.chd_current_log)) {
-		rc = llog_declare_create(env, cathandle->u.chd.chd_current_log,
-					 th);
-		if (rc)
-			GOTO(out, rc);
-		llog_declare_write_rec(env, cathandle, &lirec->lid_hdr, -1, th);
-	}
-	/* declare records in the llogs */
 	rc = llog_declare_write_rec(env, cathandle->u.chd.chd_current_log,
 				    rec, -1, th);
-	if (rc)
-		GOTO(out, rc);
-
-	next = cathandle->u.chd.chd_next_log;
-	if (next) {
-		if (!llog_exist(next)) {
-			rc = llog_declare_create(env, next, th);
-			llog_declare_write_rec(env, cathandle, &lirec->lid_hdr,
-					       -1, th);
-		}
-		/* XXX: we hope for declarations made for existing llog
-		 *	this might be not correct with some backends
-		 *	where declarations are expected against specific
-		 *	object like ZFS with full debugging enabled */
-		/*llog_declare_write_rec(env, next, rec, -1, th);*/
+	if (rc == -ESTALE && dt_object_remote(cathandle->lgh_obj)) {
+		up_read(&cathandle->lgh_lock);
+		rc = llog_cat_refresh(env, cathandle);
+		if (rc)
+			RETURN(rc);
+		goto start;
 	}
-out:
+
+#if 0
+	/*
+	 * XXX: we hope for declarations made for existing llog this might be
+	 * not correct with some backends where declarations are expected
+	 * against specific object like ZFS with full debugging enabled.
+	 */
+	rc = llog_declare_write_rec(env, cathandle->u.chd.chd_next_log, rec, -1,
+				    th);
+#endif
+unlock:
+	up_read(&cathandle->lgh_lock);
 	RETURN(rc);
 }
 EXPORT_SYMBOL(llog_cat_declare_add_rec);
@@ -457,6 +689,57 @@ out_trans:
 }
 EXPORT_SYMBOL(llog_cat_add);
 
+int llog_cat_cancel_arr_rec(const struct lu_env *env,
+			    struct llog_handle *cathandle,
+			    struct llog_logid *lgl, int count, int *index)
+{
+	struct llog_handle *loghandle;
+	int  rc;
+
+	ENTRY;
+	rc = llog_cat_id2handle(env, cathandle, &loghandle, lgl);
+	if (rc) {
+		CDEBUG(D_HA, "%s: can't find llog handle for "DFID": rc = %d\n",
+		       loghandle2name(cathandle), PLOGID(lgl), rc);
+		RETURN(rc);
+	}
+
+	if ((cathandle->lgh_ctxt->loc_flags &
+	     LLOG_CTXT_FLAG_NORMAL_FID) && !llog_exist(loghandle)) {
+		/* For update log, some of loghandles of cathandle
+		 * might not exist because remote llog creation might
+		 * be failed, so let's skip the record cancellation
+		 * for these non-exist llogs.
+		 */
+		rc = -ENOENT;
+		CDEBUG(D_HA, "%s: llog "DFID" does not exist: rc = %d\n",
+		       loghandle2name(cathandle), PLOGID(lgl), rc);
+		llog_handle_put(env, loghandle);
+		RETURN(rc);
+	}
+
+	rc = llog_cancel_arr_rec(env, loghandle, count, index);
+	if (rc == LLOG_DEL_PLAIN) { /* log has been destroyed */
+		int cat_index;
+
+		cat_index = loghandle->u.phd.phd_cookie.lgc_index;
+		rc = llog_cat_cleanup(env, cathandle, loghandle, cat_index);
+		if (rc)
+			CERROR("%s: fail to cancel catalog record: rc = %d\n",
+			       loghandle2name(cathandle), rc);
+		rc = 0;
+
+	}
+	llog_handle_put(env, loghandle);
+
+	if (rc)
+		CERROR("%s: fail to cancel %d llog-records: rc = %d\n",
+		       loghandle2name(cathandle), count, rc);
+
+	RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_cancel_arr_rec);
+
 /* For each cookie in the cookie array, we clear the log in-use bit and either:
  * - the log is empty, so mark it free in the catalog header and delete it
  * - the log is not empty, just write out the log header
@@ -470,104 +753,111 @@ int llog_cat_cancel_records(const struct lu_env *env,
 			    struct llog_handle *cathandle, int count,
 			    struct llog_cookie *cookies)
 {
-	int i, index, rc = 0, failed = 0;
+	int i, rc = 0, failed = 0;
 
 	ENTRY;
 
 	for (i = 0; i < count; i++, cookies++) {
-		struct llog_handle	*loghandle;
-		struct llog_logid	*lgl = &cookies->lgc_lgl;
-		int			 lrc;
-
-		rc = llog_cat_id2handle(env, cathandle, &loghandle, lgl);
-		if (rc) {
-			CERROR("%s: cannot find handle for llog "DOSTID": %d\n",
-			       cathandle->lgh_ctxt->loc_obd->obd_name,
-			       POSTID(&lgl->lgl_oi), rc);
-			failed++;
-			continue;
-		}
+		int lrc;
 
-		lrc = llog_cancel_rec(env, loghandle, cookies->lgc_index);
-		if (lrc == LLOG_DEL_PLAIN) { /* log has been destroyed */
-			index = loghandle->u.phd.phd_cookie.lgc_index;
-			rc = llog_cat_cleanup(env, cathandle, loghandle,
-					      index);
-		} else if (lrc == -ENOENT) {
-			if (rc == 0) /* ENOENT shouldn't rewrite any error */
-				rc = lrc;
-		} else if (lrc < 0) {
+		lrc = llog_cat_cancel_arr_rec(env, cathandle, &cookies->lgc_lgl,
+					     1, &cookies->lgc_index);
+		if (lrc) {
 			failed++;
-			rc = lrc;
+			if (!rc)
+				rc = lrc;
 		}
-		llog_handle_put(loghandle);
 	}
-	if (rc)
+	if (failed)
 		CERROR("%s: fail to cancel %d of %d llog-records: rc = %d\n",
-		       cathandle->lgh_ctxt->loc_obd->obd_name, failed, count,
-		       rc);
-
+		       loghandle2name(cathandle), failed, count, rc);
 	RETURN(rc);
 }
 EXPORT_SYMBOL(llog_cat_cancel_records);
 
-int llog_cat_process_cb(const struct lu_env *env, struct llog_handle *cat_llh,
-			struct llog_rec_hdr *rec, void *data)
+static int llog_cat_process_common(const struct lu_env *env,
+				   struct llog_handle *cat_llh,
+				   struct llog_rec_hdr *rec,
+				   struct llog_handle **llhp)
 {
-        struct llog_process_data *d = data;
-        struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
-        struct llog_handle *llh;
+	struct llog_logid_rec *lir = container_of(rec, typeof(*lir), lid_hdr);
 	struct llog_log_hdr *hdr;
-        int rc;
+	int rc;
 
-        ENTRY;
-        if (rec->lrh_type != LLOG_LOGID_MAGIC) {
-                CERROR("invalid record in catalog\n");
-                RETURN(-EINVAL);
-        }
-	CDEBUG(D_HA, "processing log "DOSTID":%x at index %u of catalog "
-	       DOSTID"\n", POSTID(&lir->lid_id.lgl_oi), lir->lid_id.lgl_ogen,
-	       rec->lrh_index, POSTID(&cat_llh->lgh_id.lgl_oi));
+	ENTRY;
+	if (rec->lrh_type != le32_to_cpu(LLOG_LOGID_MAGIC)) {
+		rc = -EINVAL;
+		CWARN("%s: invalid record in catalog "DFID": rc = %d\n",
+		      loghandle2name(cat_llh), PLOGID(&cat_llh->lgh_id), rc);
+		RETURN(rc);
+	}
+	CDEBUG(D_HA, "processing log "DFID" at index %u of catalog "DFID"\n",
+	       PLOGID(&lir->lid_id), le32_to_cpu(rec->lrh_index),
+	       PLOGID(&cat_llh->lgh_id));
 
-	rc = llog_cat_id2handle(env, cat_llh, &llh, &lir->lid_id);
+	rc = llog_cat_id2handle(env, cat_llh, llhp, &lir->lid_id);
 	if (rc) {
-		CERROR("%s: cannot find handle for llog "DOSTID": %d\n",
-		       cat_llh->lgh_ctxt->loc_obd->obd_name,
-		       POSTID(&lir->lid_id.lgl_oi), rc);
-		if (rc == -ENOENT || rc == -ESTALE) {
-			/* After a server crash, a stub of index
-			 * record in catlog could be kept, because
-			 * plain log destroy + catlog index record
-			 * deletion are not atomic. So we end up with
-			 * an index but no actual record. Destroy the
-			 * index and move on. */
-			rc = llog_cat_cleanup(env, cat_llh, NULL,
-					      rec->lrh_index);
-		}
+		/* After a server crash, a stub of index record in catlog could
+		 * be kept, because plain log destroy + catlog index record
+		 * deletion are not atomic. So we end up with an index but no
+		 * actual record. Destroy the index and move on. */
+		if (rc == -ENOENT || rc == -ESTALE)
+			rc = LLOG_DEL_RECORD;
+		else if (rc)
+			CWARN("%s: can't find llog handle "DFID": rc = %d\n",
+			      loghandle2name(cat_llh), PLOGID(&lir->lid_id),
+			      rc);
 
 		RETURN(rc);
 	}
 
 	/* clean old empty llogs, do not consider current llog in use */
-	hdr = llh->lgh_hdr;
+	/* ignore remote (lgh_obj == NULL) llogs */
+	hdr = (*llhp)->lgh_hdr;
 	if ((hdr->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
-	    hdr->llh_count == 1 &&
-	    llh != cat_llh->u.chd.chd_current_log) {
-		rc = llog_destroy(env, llh);
+	    hdr->llh_count == 1 && cat_llh->lgh_obj != NULL &&
+	    *llhp != cat_llh->u.chd.chd_current_log &&
+	    *llhp != cat_llh->u.chd.chd_next_log) {
+		rc = llog_destroy(env, *llhp);
 		if (rc)
-			CERROR("%s: fail to destroy empty log: rc = %d\n",
-			       llh->lgh_ctxt->loc_obd->obd_name, rc);
-		GOTO(out, rc = LLOG_DEL_PLAIN);
+			CWARN("%s: can't destroy empty log "DFID": rc = %d\n",
+			      loghandle2name((*llhp)), PLOGID(&lir->lid_id),
+			      rc);
+		rc = LLOG_DEL_PLAIN;
 	}
 
-	if (rec->lrh_index < d->lpd_startcat) {
-		/* Skip processing of the logs until startcat */
-		rc = 0;
-	} else if (d->lpd_startidx > 0) {
-                struct llog_process_cat_data cd;
+	RETURN(rc);
+}
+
+static int llog_cat_process_cb(const struct lu_env *env,
+			       struct llog_handle *cat_llh,
+			       struct llog_rec_hdr *rec, void *data)
+{
+	struct llog_process_data *d = data;
+	struct llog_handle *llh = NULL;
+	int rc;
+
+	ENTRY;
+
+	/* Skip processing of the logs until startcat */
+	if (rec->lrh_index < d->lpd_startcat)
+		RETURN(0);
+
+	rc = llog_cat_process_common(env, cat_llh, rec, &llh);
+	if (rc)
+		GOTO(out, rc);
+
+	if (d->lpd_startidx > 0) {
+		struct llog_process_cat_data cd = {
+			.lpcd_first_idx = 0,
+			.lpcd_last_idx = 0,
+			.lpcd_read_mode = LLOG_READ_MODE_NORMAL,
+		};
+
+		/* startidx is always associated with a catalog index */
+		if (d->lpd_startcat == rec->lrh_index)
+			cd.lpcd_first_idx = d->lpd_startidx;
 
-                cd.lpcd_first_idx = d->lpd_startidx;
-                cd.lpcd_last_idx = 0;
 		rc = llog_process_or_fork(env, llh, d->lpd_cb, d->lpd_data,
 					  &cd, false);
 		/* Continue processing the next log from idx 0 */
@@ -576,125 +866,234 @@ int llog_cat_process_cb(const struct lu_env *env, struct llog_handle *cat_llh,
 		rc = llog_process_or_fork(env, llh, d->lpd_cb, d->lpd_data,
 					  NULL, false);
 	}
+	if (rc == -ENOENT && (cat_llh->lgh_hdr->llh_flags & LLOG_F_RM_ON_ERR)) {
+		/*
+		 * plain llog is reported corrupted, so better to just remove
+		 * it if the caller is fine with that.
+		 */
+		CERROR("%s: remove corrupted/missing llog "DFID"\n",
+		       loghandle2name(cat_llh), PLOGID(&llh->lgh_id));
+		rc = LLOG_DEL_PLAIN;
+	}
 
 out:
 	/* The empty plain log was destroyed while processing */
-	if (rc == LLOG_DEL_PLAIN)
-		rc = llog_cat_cleanup(env, cat_llh, llh,
-				      llh->u.phd.phd_cookie.lgc_index);
-	llog_handle_put(llh);
+	if (rc == LLOG_DEL_PLAIN || rc == LLOG_DEL_RECORD)
+		/* clear wrong catalog entry */
+		rc = llog_cat_cleanup(env, cat_llh, llh, rec->lrh_index);
+	else if (rc == LLOG_SKIP_PLAIN)
+		/* processing callback ask to skip the llog -> continue */
+		rc = 0;
+
+	if (llh)
+		llog_handle_put(env, llh);
 
 	RETURN(rc);
 }
 
 int llog_cat_process_or_fork(const struct lu_env *env,
-			     struct llog_handle *cat_llh,
+			     struct llog_handle *cat_llh, llog_cb_t cat_cb,
 			     llog_cb_t cb, void *data, int startcat,
 			     int startidx, bool fork)
 {
-        struct llog_process_data d;
-        struct llog_log_hdr *llh = cat_llh->lgh_hdr;
-        int rc;
-        ENTRY;
+	struct llog_log_hdr *llh = cat_llh->lgh_hdr;
+	struct llog_process_data d;
+	struct llog_process_cat_data cd;
+	int rc;
 
-        LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
-        d.lpd_data = data;
-        d.lpd_cb = cb;
-        d.lpd_startcat = startcat;
-        d.lpd_startidx = startidx;
+	ENTRY;
 
-        if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
-                struct llog_process_cat_data cd;
+	LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
+	d.lpd_data = data;
+	d.lpd_cb = cb;
+
+	/* default: start from the oldest record */
+	d.lpd_startidx = 0;
+	d.lpd_startcat = llh->llh_cat_idx + 1;
+	cd.lpcd_first_idx = llh->llh_cat_idx;
+	cd.lpcd_last_idx = 0;
+	cd.lpcd_read_mode = LLOG_READ_MODE_NORMAL;
+
+	if (startcat > 0 && startcat <= llog_max_idx(llh)) {
+		/* start from a custom catalog/llog plain indexes*/
+		d.lpd_startidx = startidx;
+		d.lpd_startcat = startcat;
+		cd.lpcd_first_idx = startcat - 1;
+	} else if (startcat != 0) {
+		CWARN("%s: startcat %d out of range for catlog "DFID"\n",
+		      loghandle2name(cat_llh), startcat,
+		      PLOGID(&cat_llh->lgh_id));
+		RETURN(-EINVAL);
+	}
 
-                CWARN("catlog "DOSTID" crosses index zero\n",
-                      POSTID(&cat_llh->lgh_id.lgl_oi));
+	startcat = d.lpd_startcat;
 
-                cd.lpcd_first_idx = llh->llh_cat_idx;
-                cd.lpcd_last_idx = 0;
-		rc = llog_process_or_fork(env, cat_llh, llog_cat_process_cb,
-					  &d, &cd, fork);
-		if (rc != 0)
+	/* if startcat <= lgh_last_idx, we only need to process the first part
+	 * of the catalog (from startcat).
+	 */
+	if (llog_cat_is_wrapped(cat_llh) && startcat > cat_llh->lgh_last_idx) {
+		int cat_idx_origin = llh->llh_cat_idx;
+
+		CWARN("%s: catlog "DFID" crosses index zero\n",
+		      loghandle2name(cat_llh),
+		      PLOGID(&cat_llh->lgh_id));
+
+		/* processing the catalog part at the end */
+		rc = llog_process_or_fork(env, cat_llh, cat_cb, &d, &cd, fork);
+		if (rc)
 			RETURN(rc);
 
+		/* Reset the startcat because it has already reached catalog
+		 * bottom.
+		 * lgh_last_idx value could be increased during processing. So
+		 * we process the remaining of catalog entries to be sure.
+		 */
+		d.lpd_startcat = 1;
+		d.lpd_startidx = 0;
 		cd.lpcd_first_idx = 0;
-		cd.lpcd_last_idx = cat_llh->lgh_last_idx;
-		rc = llog_process_or_fork(env, cat_llh, llog_cat_process_cb,
-					  &d, &cd, fork);
-        } else {
-		rc = llog_process_or_fork(env, cat_llh, llog_cat_process_cb,
-					  &d, NULL, fork);
-        }
+		cd.lpcd_last_idx = max(cat_idx_origin, cat_llh->lgh_last_idx);
+	} else if (llog_cat_is_wrapped(cat_llh)) {
+		/* only process 1st part -> stop before reaching 2sd part */
+		cd.lpcd_last_idx = llh->llh_cat_idx;
+	}
 
-        RETURN(rc);
+	/* processing the catalog part at the begining */
+	rc = llog_process_or_fork(env, cat_llh, cat_cb, &d, &cd, fork);
+
+	RETURN(rc);
 }
 EXPORT_SYMBOL(llog_cat_process_or_fork);
 
+/**
+ * Process catalog records with a callback
+ *
+ * \note
+ * If "starcat = 0", this is the default processing. "startidx" argument is
+ * ignored and processing begin from the oldest record.
+ * If "startcat > 0", this is a custom starting point. Processing begin with
+ * the llog plain defined in the catalog record at index "startcat". The first
+ * llog plain record to process is at index "startidx + 1".
+ *
+ * \param env		Lustre environnement
+ * \param cat_llh	Catalog llog handler
+ * \param cb		Callback executed for each records (in llog plain files)
+ * \param data		Callback data argument
+ * \param startcat	Catalog index of the llog plain to start with.
+ * \param startidx	Index of the llog plain to start processing. The first
+ *			record to process is at startidx + 1.
+ *
+ * \retval 0 processing successfully completed
+ * \retval LLOG_PROC_BREAK processing was stopped by the callback.
+ * \retval -errno on error.
+ */
 int llog_cat_process(const struct lu_env *env, struct llog_handle *cat_llh,
 		     llog_cb_t cb, void *data, int startcat, int startidx)
 {
-	return llog_cat_process_or_fork(env, cat_llh, cb, data, startcat,
-					startidx, false);
+	return llog_cat_process_or_fork(env, cat_llh, llog_cat_process_cb,
+					cb, data, startcat, startidx, false);
 }
 EXPORT_SYMBOL(llog_cat_process);
 
+static int llog_cat_size_cb(const struct lu_env *env,
+			     struct llog_handle *cat_llh,
+			     struct llog_rec_hdr *rec, void *data)
+{
+	struct llog_process_data *d = data;
+	struct llog_handle *llh = NULL;
+	__u64 *cum_size = d->lpd_data;
+	__u64 size;
+	int rc;
+
+	ENTRY;
+	rc = llog_cat_process_common(env, cat_llh, rec, &llh);
+
+	if (rc == LLOG_DEL_PLAIN) {
+		/* empty log was deleted, don't count it */
+		rc = llog_cat_cleanup(env, cat_llh, llh,
+				      llh->u.phd.phd_cookie.lgc_index);
+	} else if (rc == LLOG_DEL_RECORD) {
+		/* clear wrong catalog entry */
+		rc = llog_cat_cleanup(env, cat_llh, NULL, rec->lrh_index);
+	} else {
+		size = llog_size(env, llh);
+		*cum_size += size;
+
+		CDEBUG(D_INFO, "Add llog entry "DFID" size=%llu, tot=%llu\n",
+		       PLOGID(&llh->lgh_id), size, *cum_size);
+	}
+
+	if (llh != NULL)
+		llog_handle_put(env, llh);
+
+	RETURN(0);
+}
+
+__u64 llog_cat_size(const struct lu_env *env, struct llog_handle *cat_llh)
+{
+	__u64 size = llog_size(env, cat_llh);
+
+	llog_cat_process_or_fork(env, cat_llh, llog_cat_size_cb,
+				 NULL, &size, 0, 0, false);
+
+	return size;
+}
+EXPORT_SYMBOL(llog_cat_size);
+
+/* currently returns the number of "free" entries in catalog,
+ * ie the available entries for a new plain LLOG file creation,
+ * even if catalog has wrapped
+ */
+__u32 llog_cat_free_space(struct llog_handle *cat_llh)
+{
+	/* simulate almost full Catalog */
+	if (CFS_FAIL_CHECK(OBD_FAIL_CAT_FREE_RECORDS))
+		return cfs_fail_val;
+
+	if (cat_llh->lgh_hdr->llh_count == 1)
+		return llog_max_idx(cat_llh->lgh_hdr);
+
+	if (cat_llh->lgh_last_idx > cat_llh->lgh_hdr->llh_cat_idx)
+		return llog_max_idx(cat_llh->lgh_hdr) +
+		       cat_llh->lgh_hdr->llh_cat_idx - cat_llh->lgh_last_idx;
+
+	/* catalog is presently wrapped */
+	return cat_llh->lgh_hdr->llh_cat_idx - cat_llh->lgh_last_idx;
+}
+EXPORT_SYMBOL(llog_cat_free_space);
+
 static int llog_cat_reverse_process_cb(const struct lu_env *env,
 				       struct llog_handle *cat_llh,
 				       struct llog_rec_hdr *rec, void *data)
 {
 	struct llog_process_data *d = data;
-	struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
 	struct llog_handle *llh;
-	struct llog_log_hdr *hdr;
 	int rc;
 
-	if (le32_to_cpu(rec->lrh_type) != LLOG_LOGID_MAGIC) {
-		CERROR("invalid record in catalog\n");
-		RETURN(-EINVAL);
-	}
-	CDEBUG(D_HA, "processing log "DOSTID":%x at index %u of catalog "
-	       DOSTID"\n", POSTID(&lir->lid_id.lgl_oi), lir->lid_id.lgl_ogen,
-	       le32_to_cpu(rec->lrh_index), POSTID(&cat_llh->lgh_id.lgl_oi));
-
-	rc = llog_cat_id2handle(env, cat_llh, &llh, &lir->lid_id);
-	if (rc) {
-		CERROR("%s: cannot find handle for llog "DOSTID": %d\n",
-		       cat_llh->lgh_ctxt->loc_obd->obd_name,
-		       POSTID(&lir->lid_id.lgl_oi), rc);
-		if (rc == -ENOENT || rc == -ESTALE) {
-			/* After a server crash, a stub of index
-			 * record in catlog could be kept, because
-			 * plain log destroy + catlog index record
-			 * deletion are not atomic. So we end up with
-			 * an index but no actual record. Destroy the
-			 * index and move on. */
-			rc = llog_cat_cleanup(env, cat_llh, NULL,
-					      rec->lrh_index);
-		}
-
-		RETURN(rc);
-	}
+	ENTRY;
+	rc = llog_cat_process_common(env, cat_llh, rec, &llh);
 
-	/* clean old empty llogs, do not consider current llog in use */
-	hdr = llh->lgh_hdr;
-	if ((hdr->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
-	    hdr->llh_count == 1 &&
-	    llh != cat_llh->u.chd.chd_current_log) {
-		rc = llog_destroy(env, llh);
-		if (rc)
-			CERROR("%s: fail to destroy empty log: rc = %d\n",
-			       llh->lgh_ctxt->loc_obd->obd_name, rc);
-		GOTO(out, rc = LLOG_DEL_PLAIN);
+	/* The empty plain log was destroyed while processing */
+	if (rc == LLOG_DEL_PLAIN) {
+		rc = llog_cat_cleanup(env, cat_llh, llh,
+				      llh->u.phd.phd_cookie.lgc_index);
+	} else if (rc == LLOG_DEL_RECORD) {
+		/* clear wrong catalog entry */
+		rc = llog_cat_cleanup(env, cat_llh, NULL, rec->lrh_index);
+	} else if (rc == LLOG_SKIP_PLAIN) {
+		/* processing callback ask to skip the llog -> continue */
+		rc = 0;
 	}
+	if (rc)
+		RETURN(rc);
 
 	rc = llog_reverse_process(env, llh, d->lpd_cb, d->lpd_data, NULL);
 
-out:
 	/* The empty plain was destroyed while processing */
 	if (rc == LLOG_DEL_PLAIN)
 		rc = llog_cat_cleanup(env, cat_llh, llh,
 				      llh->u.phd.phd_cookie.lgc_index);
 
-	llog_handle_put(llh);
+	llog_handle_put(env, llh);
 	RETURN(rc);
 }
 
@@ -709,15 +1108,18 @@ int llog_cat_reverse_process(const struct lu_env *env,
         ENTRY;
 
         LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
+	cd.lpcd_read_mode = LLOG_READ_MODE_NORMAL;
         d.lpd_data = data;
         d.lpd_cb = cb;
 
-	if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
-		CWARN("catalog "DOSTID" crosses index zero\n",
-		      POSTID(&cat_llh->lgh_id.lgl_oi));
+	if (llh->llh_cat_idx >= cat_llh->lgh_last_idx &&
+	    llh->llh_count > 1) {
+		CWARN("%s: catalog "DFID" crosses index zero\n",
+		      loghandle2name(cat_llh),
+		      PLOGID(&cat_llh->lgh_id));
 
-                cd.lpcd_first_idx = 0;
-                cd.lpcd_last_idx = cat_llh->lgh_last_idx;
+		cd.lpcd_first_idx = 0;
+		cd.lpcd_last_idx = cat_llh->lgh_last_idx;
 		rc = llog_reverse_process(env, cat_llh,
 					  llog_cat_reverse_process_cb,
 					  &d, &cd);
@@ -739,33 +1141,41 @@ int llog_cat_reverse_process(const struct lu_env *env,
 }
 EXPORT_SYMBOL(llog_cat_reverse_process);
 
-int llog_cat_set_first_idx(struct llog_handle *cathandle, int index)
+static int llog_cat_set_first_idx(struct llog_handle *cathandle, int idx)
 {
-        struct llog_log_hdr *llh = cathandle->lgh_hdr;
-        int i, bitmap_size, idx;
-        ENTRY;
+	struct llog_log_hdr *llh = cathandle->lgh_hdr;
+	int idx_nbr;
 
-        bitmap_size = LLOG_BITMAP_SIZE(llh);
-        if (llh->llh_cat_idx == (index - 1)) {
-                idx = llh->llh_cat_idx + 1;
-                llh->llh_cat_idx = idx;
-                if (idx == cathandle->lgh_last_idx)
-                        goto out;
-                for (i = (index + 1) % bitmap_size;
-                     i != cathandle->lgh_last_idx;
-                     i = (i + 1) % bitmap_size) {
-                        if (!ext2_test_bit(i, llh->llh_bitmap)) {
-                                idx = llh->llh_cat_idx + 1;
-                                llh->llh_cat_idx = idx;
-                        } else if (i == 0) {
-                                llh->llh_cat_idx = 0;
-                        } else {
-                                break;
-                        }
-                }
-out:
-		CDEBUG(D_RPCTRACE, "set catlog "DOSTID" first idx %u\n",
-		       POSTID(&cathandle->lgh_id.lgl_oi), llh->llh_cat_idx);
+	ENTRY;
+
+	idx_nbr = llog_max_idx(llh) + 1;
+	/*
+	 * The llh_cat_idx equals to the first used index minus 1
+	 * so if we canceled the first index then llh_cat_idx
+	 * must be renewed.
+	 */
+	if (llh->llh_cat_idx == (idx - 1)) {
+		llh->llh_cat_idx = idx;
+
+		while (idx != cathandle->lgh_last_idx) {
+			idx = (idx + 1) % idx_nbr;
+			if (!test_bit_le(idx, LLOG_HDR_BITMAP(llh))) {
+				/* update llh_cat_idx for each unset bit,
+				 * expecting the next one is set */
+				llh->llh_cat_idx = idx;
+			} else if (idx == 0) {
+				/* skip header bit */
+				llh->llh_cat_idx = 0;
+				continue;
+			} else {
+				/* the first index is found */
+				break;
+			}
+		}
+
+		CDEBUG(D_HA, "catlog "DFID" first idx %u, last_idx %u\n",
+		       PLOGID(&cathandle->lgh_id), llh->llh_cat_idx,
+		       cathandle->lgh_last_idx);
 	}
 
 	RETURN(0);
@@ -786,79 +1196,48 @@ int llog_cat_cleanup(const struct lu_env *env, struct llog_handle *cathandle,
 			cathandle->u.chd.chd_current_log = NULL;
 		list_del_init(&loghandle->u.phd.phd_entry);
 		up_write(&cathandle->lgh_lock);
-		LASSERT(index == loghandle->u.phd.phd_cookie.lgc_index);
+		LASSERT(index == loghandle->u.phd.phd_cookie.lgc_index ||
+			loghandle->u.phd.phd_cookie.lgc_index == 0);
 		/* llog was opened and keep in a list, close it now */
 		llog_close(env, loghandle);
 	}
+
+	/* do not attempt to cleanup on-disk llog if on client side */
+	if (cathandle->lgh_obj == NULL)
+		return 0;
+
 	/* remove plain llog entry from catalog by index */
 	llog_cat_set_first_idx(cathandle, index);
 	rc = llog_cancel_rec(env, cathandle, index);
-	if (rc == 0)
-		CDEBUG(D_HA, "cancel plain log at index"
-		       " %u of catalog "DOSTID"\n",
-		       index, POSTID(&cathandle->lgh_id.lgl_oi));
+	if (!rc && loghandle)
+		CDEBUG(D_HA,
+		       "cancel plain log "DFID" at index %u of catalog "DFID"\n",
+		       PLOGID(&loghandle->lgh_id), index,
+		       PLOGID(&cathandle->lgh_id));
 	return rc;
 }
 
-int cat_cancel_cb(const struct lu_env *env, struct llog_handle *cathandle,
-		  struct llog_rec_hdr *rec, void *data)
+/* retain log in catalog, and zap it if log is empty */
+int llog_cat_retain_cb(const struct lu_env *env, struct llog_handle *cat,
+		       struct llog_rec_hdr *rec, void *data)
 {
-	struct llog_logid_rec	*lir = (struct llog_logid_rec *)rec;
-	struct llog_handle	*loghandle;
-	struct llog_log_hdr	*llh;
-	int			 rc;
-
-	ENTRY;
-
-	if (rec->lrh_type != LLOG_LOGID_MAGIC) {
-		CERROR("invalid record in catalog\n");
-		RETURN(-EINVAL);
-	}
+	struct llog_handle *log = NULL;
+	int rc;
 
-	CDEBUG(D_HA, "processing log "DOSTID":%x at index %u of catalog "
-	       DOSTID"\n", POSTID(&lir->lid_id.lgl_oi), lir->lid_id.lgl_ogen,
-	       rec->lrh_index, POSTID(&cathandle->lgh_id.lgl_oi));
+	rc = llog_cat_process_common(env, cat, rec, &log);
 
-	rc = llog_cat_id2handle(env, cathandle, &loghandle, &lir->lid_id);
-	if (rc) {
-		CERROR("%s: cannot find handle for llog "DOSTID": %d\n",
-		       cathandle->lgh_ctxt->loc_obd->obd_name,
-		       POSTID(&lir->lid_id.lgl_oi), rc);
-		if (rc == -ENOENT || rc == -ESTALE) {
-			/* remove index from catalog */
-			llog_cat_cleanup(env, cathandle, NULL, rec->lrh_index);
-		}
-		RETURN(rc);
-	}
-
-	llh = loghandle->lgh_hdr;
-	if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
-	    (llh->llh_count == 1)) {
-		rc = llog_destroy(env, loghandle);
-		if (rc)
-			CERROR("%s: fail to destroy empty log: rc = %d\n",
-			       loghandle->lgh_ctxt->loc_obd->obd_name, rc);
+	/* The empty plain log was destroyed while processing */
+	if (rc == LLOG_DEL_PLAIN || rc == LLOG_DEL_RECORD)
+		/* clear wrong catalog entry */
+		rc = llog_cat_cleanup(env, cat, log, rec->lrh_index);
+	else if (!rc)
+		llog_retain(env, log);
 
-		llog_cat_cleanup(env, cathandle, loghandle,
-				 loghandle->u.phd.phd_cookie.lgc_index);
-	}
-	llog_handle_put(loghandle);
+	if (log)
+		llog_handle_put(env, log);
 
-	RETURN(rc);
+	return rc;
 }
-EXPORT_SYMBOL(cat_cancel_cb);
-
-/* helper to initialize catalog llog and process it to cancel */
-int llog_cat_init_and_process(const struct lu_env *env,
-			      struct llog_handle *llh)
-{
-	int rc;
+EXPORT_SYMBOL(llog_cat_retain_cb);
 
-	rc = llog_init_handle(env, llh, LLOG_F_IS_CAT, NULL);
-	if (rc)
-		RETURN(rc);
-
-	RETURN(0);
-}
-EXPORT_SYMBOL(llog_cat_init_and_process);