staging/lustre/llog: MGC to use OSD API for backup logs

MGC uses lvfs API to access local llogs blocking removal of old code

- llog_is_empty() and llog_backup() are introduced

Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2059
Lustre-change: http://review.whamcloud.com/5049
Cc: Levente Kurusa <levex@linux.com>
Signed-off-by: Mikhail Pershin <mike.pershin@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
[pick client side change only -- Peng Tao]
Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/dt_object.h

@@ -692,7 +692,7 @@ struct local_oid_storage {
 	struct dt_object *los_obj;
 
 	/* data used to generate new fids */
-	struct mutex	 los_id_lock;
+	struct mutex	  los_id_lock;
 	__u64		  los_seq;
 	__u32		  los_last_oid;
 };

drivers/staging/lustre/lustre/include/lustre_log.h

@@ -136,7 +136,11 @@ int llog_open(const struct lu_env *env, struct llog_ctxt *ctxt,
 	      struct llog_handle **lgh, struct llog_logid *logid,
 	      char *name, enum llog_open_param open_param);
 int llog_close(const struct lu_env *env, struct llog_handle *cathandle);
-int llog_get_size(struct llog_handle *loghandle);
+int llog_is_empty(const struct lu_env *env, struct llog_ctxt *ctxt,
+		  char *name);
+int llog_backup(const struct lu_env *env, struct obd_device *obd,
+		struct llog_ctxt *ctxt, struct llog_ctxt *bak_ctxt,
+		char *name, char *backup);
 
 /* llog_process flags */
 #define LLOG_FLAG_NODEAMON 0x0001
@@ -382,6 +386,13 @@ static inline int llog_data_len(int len)
 	return cfs_size_round(len);
 }
 
+static inline int llog_get_size(struct llog_handle *loghandle)
+{
+	if (loghandle && loghandle->lgh_hdr)
+		return loghandle->lgh_hdr->llh_count;
+	return 0;
+}
+
 static inline struct llog_ctxt *llog_ctxt_get(struct llog_ctxt *ctxt)
 {
 	atomic_inc(&ctxt->loc_refcount);

drivers/staging/lustre/lustre/include/obd.h

@@ -399,8 +399,8 @@ struct client_obd {
 
 	/* mgc datastruct */
 	struct semaphore	 cl_mgc_sem;
-	struct vfsmount	 *cl_mgc_vfsmnt;
-	struct dentry	   *cl_mgc_configs_dir;
+	struct local_oid_storage *cl_mgc_los;
+	struct dt_object	*cl_mgc_configs_dir;
 	atomic_t	     cl_mgc_refcount;
 	struct obd_export       *cl_mgc_mgsexp;
 

drivers/staging/lustre/lustre/mgc/libmgc.c

@@ -99,11 +99,8 @@ static int mgc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 
 static int mgc_cleanup(struct obd_device *obd)
 {
-	struct client_obd *cli = &obd->u.cli;
 	int rc;
 
-	LASSERT(cli->cl_mgc_vfsmnt == NULL);
-
 	ptlrpcd_decref();
 
 	rc = client_obd_cleanup(obd);

drivers/staging/lustre/lustre/obdclass/llog.c

@@ -265,31 +265,6 @@ int llog_init_handle(const struct lu_env *env, struct llog_handle *handle,
 }
 EXPORT_SYMBOL(llog_init_handle);
 
-int llog_copy_handler(const struct lu_env *env,
-		      struct llog_handle *llh,
-		      struct llog_rec_hdr *rec,
-		      void *data)
-{
-	struct llog_rec_hdr local_rec = *rec;
-	struct llog_handle *local_llh = (struct llog_handle *)data;
-	char *cfg_buf = (char*) (rec + 1);
-	struct lustre_cfg *lcfg;
-	int rc = 0;
-
-	/* Append all records */
-	local_rec.lrh_len -= sizeof(*rec) + sizeof(struct llog_rec_tail);
-	rc = llog_write(env, local_llh, &local_rec, NULL, 0,
-			(void *)cfg_buf, -1);
-
-	lcfg = (struct lustre_cfg *)cfg_buf;
-	CDEBUG(D_INFO, "idx=%d, rc=%d, len=%d, cmd %x %s %s\n",
-	       rec->lrh_index, rc, rec->lrh_len, lcfg->lcfg_command,
-	       lustre_cfg_string(lcfg, 0), lustre_cfg_string(lcfg, 1));
-
-	return rc;
-}
-EXPORT_SYMBOL(llog_copy_handler);
-
 static int llog_process_thread(void *arg)
 {
 	struct llog_process_info	*lpi = arg;
@@ -493,14 +468,6 @@ int llog_process(const struct lu_env *env, struct llog_handle *loghandle,
 }
 EXPORT_SYMBOL(llog_process);
 
-inline int llog_get_size(struct llog_handle *loghandle)
-{
-	if (loghandle && loghandle->lgh_hdr)
-		return loghandle->lgh_hdr->llh_count;
-	return 0;
-}
-EXPORT_SYMBOL(llog_get_size);
-
 int llog_reverse_process(const struct lu_env *env,
 			 struct llog_handle *loghandle, llog_cb_t cb,
 			 void *data, void *catdata)
@@ -767,8 +734,9 @@ int llog_open_create(const struct lu_env *env, struct llog_ctxt *ctxt,
 		     struct llog_handle **res, struct llog_logid *logid,
 		     char *name)
 {
-	struct thandle	*th;
-	int		 rc;
+	struct dt_device	*d;
+	struct thandle		*th;
+	int			 rc;
 
 	rc = llog_open(env, ctxt, res, logid, name, LLOG_OPEN_NEW);
 	if (rc)
@@ -777,27 +745,21 @@ int llog_open_create(const struct lu_env *env, struct llog_ctxt *ctxt,
 	if (llog_exist(*res))
 		return 0;
 
-	if ((*res)->lgh_obj != NULL) {
-		struct dt_device *d;
+	LASSERT((*res)->lgh_obj != NULL);
 
-		d = lu2dt_dev((*res)->lgh_obj->do_lu.lo_dev);
+	d = lu2dt_dev((*res)->lgh_obj->do_lu.lo_dev);
 
-		th = dt_trans_create(env, d);
-		if (IS_ERR(th))
-			GOTO(out, rc = PTR_ERR(th));
+	th = dt_trans_create(env, d);
+	if (IS_ERR(th))
+		GOTO(out, rc = PTR_ERR(th));
 
-		rc = llog_declare_create(env, *res, th);
-		if (rc == 0) {
-			rc = dt_trans_start_local(env, d, th);
-			if (rc == 0)
-				rc = llog_create(env, *res, th);
-		}
-		dt_trans_stop(env, d, th);
-	} else {
-		/* lvfs compat code */
-		LASSERT((*res)->lgh_file == NULL);
-		rc = llog_create(env, *res, NULL);
+	rc = llog_declare_create(env, *res, th);
+	if (rc == 0) {
+		rc = dt_trans_start_local(env, d, th);
+		if (rc == 0)
+			rc = llog_create(env, *res, th);
 	}
+	dt_trans_stop(env, d, th);
 out:
 	if (rc)
 		llog_close(env, *res);
@@ -842,41 +804,34 @@ int llog_write(const struct lu_env *env, struct llog_handle *loghandle,
 	       struct llog_rec_hdr *rec, struct llog_cookie *reccookie,
 	       int cookiecount, void *buf, int idx)
 {
-	int rc;
+	struct dt_device	*dt;
+	struct thandle		*th;
+	int			 rc;
 
 	LASSERT(loghandle);
 	LASSERT(loghandle->lgh_ctxt);
+	LASSERT(loghandle->lgh_obj != NULL);
 
-	if (loghandle->lgh_obj != NULL) {
-		struct dt_device	*dt;
-		struct thandle		*th;
-
-		dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
+	dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
 
-		th = dt_trans_create(env, dt);
-		if (IS_ERR(th))
-			return PTR_ERR(th);
+	th = dt_trans_create(env, dt);
+	if (IS_ERR(th))
+		return PTR_ERR(th);
 
-		rc = llog_declare_write_rec(env, loghandle, rec, idx, th);
-		if (rc)
-			GOTO(out_trans, rc);
+	rc = llog_declare_write_rec(env, loghandle, rec, idx, th);
+	if (rc)
+		GOTO(out_trans, rc);
 
-		rc = dt_trans_start_local(env, dt, th);
-		if (rc)
-			GOTO(out_trans, rc);
+	rc = dt_trans_start_local(env, dt, th);
+	if (rc)
+		GOTO(out_trans, rc);
 
-		down_write(&loghandle->lgh_lock);
-		rc = llog_write_rec(env, loghandle, rec, reccookie,
-				    cookiecount, buf, idx, th);
-		up_write(&loghandle->lgh_lock);
+	down_write(&loghandle->lgh_lock);
+	rc = llog_write_rec(env, loghandle, rec, reccookie,
+			    cookiecount, buf, idx, th);
+	up_write(&loghandle->lgh_lock);
 out_trans:
-		dt_trans_stop(env, dt, th);
-	} else { /* lvfs compatibility */
-		down_write(&loghandle->lgh_lock);
-		rc = llog_write_rec(env, loghandle, rec, reccookie,
-				    cookiecount, buf, idx, NULL);
-		up_write(&loghandle->lgh_lock);
-	}
+	dt_trans_stop(env, dt, th);
 	return rc;
 }
 EXPORT_SYMBOL(llog_write);
@@ -932,3 +887,104 @@ int llog_close(const struct lu_env *env, struct llog_handle *loghandle)
 	return rc;
 }
 EXPORT_SYMBOL(llog_close);
+
+int llog_is_empty(const struct lu_env *env, struct llog_ctxt *ctxt,
+		  char *name)
+{
+	struct llog_handle	*llh;
+	int			 rc = 0;
+
+	rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
+	if (rc < 0) {
+		if (likely(rc == -ENOENT))
+			rc = 0;
+		GOTO(out, rc);
+	}
+
+	rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
+	if (rc)
+		GOTO(out_close, rc);
+	rc = llog_get_size(llh);
+
+out_close:
+	llog_close(env, llh);
+out:
+	/* header is record 1 */
+	return rc <= 1;
+}
+EXPORT_SYMBOL(llog_is_empty);
+
+int llog_copy_handler(const struct lu_env *env, struct llog_handle *llh,
+		      struct llog_rec_hdr *rec, void *data)
+{
+	struct llog_handle	*copy_llh = data;
+
+	/* Append all records */
+	return llog_write(env, copy_llh, rec, NULL, 0, NULL, -1);
+}
+EXPORT_SYMBOL(llog_copy_handler);
+
+/* backup plain llog */
+int llog_backup(const struct lu_env *env, struct obd_device *obd,
+		struct llog_ctxt *ctxt, struct llog_ctxt *bctxt,
+		char *name, char *backup)
+{
+	struct llog_handle	*llh, *bllh;
+	int			 rc;
+
+
+
+	/* open original log */
+	rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
+	if (rc < 0) {
+		/* the -ENOENT case is also reported to the caller
+		 * but silently so it should handle that if needed.
+		 */
+		if (rc != -ENOENT)
+			CERROR("%s: failed to open log %s: rc = %d\n",
+			       obd->obd_name, name, rc);
+		return rc;
+	}
+
+	rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
+	if (rc)
+		GOTO(out_close, rc);
+
+	/* Make sure there's no old backup log */
+	rc = llog_erase(env, bctxt, NULL, backup);
+	if (rc < 0 && rc != -ENOENT)
+		GOTO(out_close, rc);
+
+	/* open backup log */
+	rc = llog_open_create(env, bctxt, &bllh, NULL, backup);
+	if (rc) {
+		CERROR("%s: failed to open backup logfile %s: rc = %d\n",
+		       obd->obd_name, backup, rc);
+		GOTO(out_close, rc);
+	}
+
+	/* check that backup llog is not the same object as original one */
+	if (llh->lgh_obj == bllh->lgh_obj) {
+		CERROR("%s: backup llog %s to itself (%s), objects %p/%p\n",
+		       obd->obd_name, name, backup, llh->lgh_obj,
+		       bllh->lgh_obj);
+		GOTO(out_backup, rc = -EEXIST);
+	}
+
+	rc = llog_init_handle(env, bllh, LLOG_F_IS_PLAIN, NULL);
+	if (rc)
+		GOTO(out_backup, rc);
+
+	/* Copy log record by record */
+	rc = llog_process_or_fork(env, llh, llog_copy_handler, (void *)bllh,
+				  NULL, false);
+	if (rc)
+		CERROR("%s: failed to backup log %s: rc = %d\n",
+		       obd->obd_name, name, rc);
+out_backup:
+	llog_close(env, bllh);
+out_close:
+	llog_close(env, llh);
+	return rc;
+}
+EXPORT_SYMBOL(llog_backup);

drivers/staging/lustre/lustre/obdclass/local_storage.c

@@ -855,9 +855,12 @@ int local_oid_storage_init(const struct lu_env *env, struct dt_device *dev,
 		(*los)->los_seq = fid_seq(first_fid);
 		(*los)->los_last_oid = le64_to_cpu(lastid);
 		(*los)->los_obj = o;
-		/* read value should not be less than initial one */
-		LASSERTF((*los)->los_last_oid >= first_oid, "%u < %u\n",
-			 (*los)->los_last_oid, first_oid);
+		/* Read value should not be less than initial one
+		 * but possible after upgrade from older fs.
+		 * In this case just switch to the first_oid in memory and
+		 * it will be updated on disk with first object generated */
+		if ((*los)->los_last_oid < first_oid)
+			(*los)->los_last_oid = first_oid;
 	}
 out:
 	mutex_unlock(&ls->ls_los_mutex);

drivers/staging/lustre/lustre/obdclass/local_storage.h

@@ -29,6 +29,8 @@
  *
  * Author: Mikhail Pershin <mike.pershin@intel.com>
  */
+#ifndef __LOCAL_STORAGE_H
+#define __LOCAL_STORAGE_H
 
 #include <dt_object.h>
 #include <obd.h>
@@ -86,3 +88,4 @@ struct los_ondisk {
 };
 
 #define LOS_MAGIC	0xdecafbee
+#endif

drivers/staging/lustre/lustre/obdclass/lu_object.c

@@ -429,7 +429,7 @@ LU_KEY_INIT_FINI(lu_global, struct lu_cdebug_data);
  */
 struct lu_context_key lu_global_key = {
 	.lct_tags = LCT_MD_THREAD | LCT_DT_THREAD |
-		    LCT_MG_THREAD | LCT_CL_THREAD,
+		    LCT_MG_THREAD | LCT_CL_THREAD | LCT_LOCAL,
 	.lct_init = lu_global_key_init,
 	.lct_fini = lu_global_key_fini
 };

drivers/staging/lustre/lustre/obdclass/obd_mount.c

@@ -631,6 +631,9 @@ int lustre_put_lsi(struct super_block *sb)
 	CDEBUG(D_MOUNT, "put %p %d\n", sb, atomic_read(&lsi->lsi_mounts));
 	if (atomic_dec_and_test(&lsi->lsi_mounts)) {
 		if (IS_SERVER(lsi) && lsi->lsi_osd_exp) {
+			lu_device_put(&lsi->lsi_dt_dev->dd_lu_dev);
+			lsi->lsi_osd_exp->exp_obd->obd_lvfs_ctxt.dt = NULL;
+			lsi->lsi_dt_dev = NULL;
 			obd_disconnect(lsi->lsi_osd_exp);
 			/* wait till OSD is gone */
 			obd_zombie_barrier();