+
+/**
+ * new llog API
+ *
+ * API functions:
+ * llog_open - open llog, may not exist
+ * llog_exist - check if llog exists
+ * llog_close - close opened llog, pair for open, frees llog_handle
+ * llog_declare_create - declare llog creation
+ * llog_create - create new llog on disk, need transaction handle
+ * llog_declare_write_rec - declaration of llog write
+ * llog_write_rec - write llog record on disk, need transaction handle
+ * llog_declare_add - declare llog catalog record addition
+ * llog_add - add llog record in catalog, need transaction handle
+ */
+int llog_exist(struct llog_handle *loghandle)
+{
+ struct llog_operations *lop;
+ int rc;
+
+ ENTRY;
+
+ rc = llog_handle2ops(loghandle, &lop);
+ if (rc)
+ RETURN(rc);
+ if (lop->lop_exist == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ rc = lop->lop_exist(loghandle);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_exist);
+
+int llog_declare_create(const struct lu_env *env,
+ struct llog_handle *loghandle, struct thandle *th)
+{
+ struct llog_operations *lop;
+ int raised, rc;
+
+ ENTRY;
+
+ rc = llog_handle2ops(loghandle, &lop);
+ if (rc)
+ RETURN(rc);
+ if (lop->lop_declare_create == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lop->lop_declare_create(env, loghandle, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_declare_create);
+
+int llog_create(const struct lu_env *env, struct llog_handle *handle,
+ struct thandle *th)
+{
+ struct llog_operations *lop;
+ int raised, rc;
+
+ ENTRY;
+
+ rc = llog_handle2ops(handle, &lop);
+ if (rc)
+ RETURN(rc);
+ if (lop->lop_create == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lop->lop_create(env, handle, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_create);
+
+int llog_declare_write_rec(const struct lu_env *env,
+ struct llog_handle *handle,
+ struct llog_rec_hdr *rec, int idx,
+ struct thandle *th)
+{
+ struct llog_operations *lop;
+ int raised, rc;
+
+ ENTRY;
+
+ rc = llog_handle2ops(handle, &lop);
+ if (rc)
+ RETURN(rc);
+ LASSERT(lop);
+ if (lop->lop_declare_write_rec == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lop->lop_declare_write_rec(env, handle, rec, idx, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_declare_write_rec);
+
+int llog_write_rec(const struct lu_env *env, struct llog_handle *handle,
+ struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
+ int numcookies, void *buf, int idx, struct thandle *th)
+{
+ struct llog_operations *lop;
+ int raised, rc, buflen;
+
+ ENTRY;
+
+ rc = llog_handle2ops(handle, &lop);
+ if (rc)
+ RETURN(rc);
+
+ LASSERT(lop);
+ if (lop->lop_write_rec == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ if (buf)
+ buflen = rec->lrh_len + sizeof(struct llog_rec_hdr) +
+ sizeof(struct llog_rec_tail);
+ else
+ buflen = rec->lrh_len;
+ LASSERT(cfs_size_round(buflen) == buflen);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lop->lop_write_rec(env, handle, rec, logcookies, numcookies,
+ buf, idx, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_write_rec);
+
+int llog_add(const struct lu_env *env, struct llog_handle *lgh,
+ struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
+ void *buf, struct thandle *th)
+{
+ int raised, rc;
+
+ ENTRY;
+
+ if (lgh->lgh_logops->lop_add == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lgh->lgh_logops->lop_add(env, lgh, rec, logcookies, buf, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_add);
+
+int llog_declare_add(const struct lu_env *env, struct llog_handle *lgh,
+ struct llog_rec_hdr *rec, struct thandle *th)
+{
+ int raised, rc;
+
+ ENTRY;
+
+ if (lgh->lgh_logops->lop_declare_add == NULL)
+ RETURN(-EOPNOTSUPP);
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = lgh->lgh_logops->lop_declare_add(env, lgh, rec, th);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_declare_add);
+
+/**
+ * Helper function to open llog or create it if doesn't exist.
+ * It hides all transaction handling from caller.
+ */
+int llog_open_create(const struct lu_env *env, struct llog_ctxt *ctxt,
+ struct llog_handle **res, struct llog_logid *logid,
+ char *name)
+{
+ struct dt_device *d;
+ struct thandle *th;
+ int rc;
+
+ ENTRY;
+
+ rc = llog_open(env, ctxt, res, logid, name, LLOG_OPEN_NEW);
+ if (rc)
+ RETURN(rc);
+
+ if (llog_exist(*res))
+ RETURN(0);
+
+ LASSERT((*res)->lgh_obj != NULL);
+
+ 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));
+
+ 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);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_open_create);
+
+/**
+ * Helper function to delete existent llog.
+ */
+int llog_erase(const struct lu_env *env, struct llog_ctxt *ctxt,
+ struct llog_logid *logid, char *name)
+{
+ struct llog_handle *handle;
+ int rc = 0, rc2;
+
+ ENTRY;
+
+ /* nothing to erase */
+ if (name == NULL && logid == NULL)
+ RETURN(0);
+
+ rc = llog_open(env, ctxt, &handle, logid, name, LLOG_OPEN_EXISTS);
+ if (rc < 0)
+ RETURN(rc);
+
+ rc = llog_init_handle(env, handle, LLOG_F_IS_PLAIN, NULL);
+ if (rc == 0)
+ rc = llog_destroy(env, handle);
+
+ rc2 = llog_close(env, handle);
+ if (rc == 0)
+ rc = rc2;
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_erase);
+
+/*
+ * Helper function for write record in llog.
+ * It hides all transaction handling from caller.
+ * Valid only with local llog.
+ */
+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)
+{
+ struct dt_device *dt;
+ struct thandle *th;
+ int rc;
+
+ ENTRY;
+
+ LASSERT(loghandle);
+ LASSERT(loghandle->lgh_ctxt);
+ LASSERT(loghandle->lgh_obj != NULL);
+
+ dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
+
+ 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 = 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);
+out_trans:
+ dt_trans_stop(env, dt, th);
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_write);
+
+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 raised;
+ int rc;
+
+ ENTRY;
+
+ LASSERT(ctxt);
+ LASSERT(ctxt->loc_logops);
+
+ if (ctxt->loc_logops->lop_open == NULL) {
+ *lgh = NULL;
+ RETURN(-EOPNOTSUPP);
+ }
+
+ *lgh = llog_alloc_handle();
+ if (*lgh == NULL)
+ RETURN(-ENOMEM);
+ (*lgh)->lgh_ctxt = ctxt;
+ (*lgh)->lgh_logops = ctxt->loc_logops;
+
+ raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
+ if (!raised)
+ cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
+ rc = ctxt->loc_logops->lop_open(env, *lgh, logid, name, open_param);
+ if (!raised)
+ cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
+ if (rc) {
+ llog_free_handle(*lgh);
+ *lgh = NULL;
+ }
+ RETURN(rc);
+}
+EXPORT_SYMBOL(llog_open);
+
+int llog_close(const struct lu_env *env, struct llog_handle *loghandle)
+{
+ struct llog_operations *lop;
+ int rc;
+
+ ENTRY;
+
+ rc = llog_handle2ops(loghandle, &lop);
+ if (rc)
+ GOTO(out, rc);
+ if (lop->lop_close == NULL)
+ GOTO(out, rc = -EOPNOTSUPP);
+ rc = lop->lop_close(env, loghandle);
+out:
+ llog_handle_put(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;
+
+ ENTRY;
+
+ /* 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);