re-add files that were erroneously deleted on HEAD

lustre/obdclass/llog.c

+/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
+ * vim:expandtab:shiftwidth=8:tabstop=8:
+ *
+ *  Copyright (C) 2001-2003 Cluster File Systems, Inc.
+ *   Author: Andreas Dilger <adilger@clusterfs.com>
+ *
+ *   This file is part of Lustre, http://www.lustre.org.
+ *
+ *   Lustre is free software; you can redistribute it and/or
+ *   modify it under the terms of version 2 of the GNU General Public
+ *   License as published by the Free Software Foundation.
+ *
+ *   Lustre is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with Lustre; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * OST<->MDS recovery logging infrastructure.
+ *
+ * Invariants in implementation:
+ * - we do not share logs among different OST<->MDS connections, so that
+ *   if an OST or MDS fails it need only look at log(s) relevant to itself
+ */
+
+#define DEBUG_SUBSYSTEM S_LOG
+
+#ifndef EXPORT_SYMTAB
+#define EXPORT_SYMTAB
+#endif
+
+#ifdef __KERNEL__
+#include <linux/fs.h>
+#else
+#include <liblustre.h>
+#endif
+
+#include <linux/obd_class.h>
+#include <linux/lustre_log.h>
+#include <portals/list.h>
+
+/* Allocate a new log or catalog handle */
+struct llog_handle *llog_alloc_handle(void)
+{
+        struct llog_handle *loghandle;
+        ENTRY;
+
+        OBD_ALLOC(loghandle, sizeof(*loghandle));
+        if (loghandle == NULL)
+                RETURN(ERR_PTR(-ENOMEM));
+
+        init_rwsem(&loghandle->lgh_lock);
+
+        RETURN(loghandle);
+}
+EXPORT_SYMBOL(llog_alloc_handle);
+
+
+void llog_free_handle(struct llog_handle *loghandle)
+{
+        if (!loghandle)
+                return;
+
+        if (!loghandle->lgh_hdr)
+                goto out;
+        if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_PLAIN)
+                list_del_init(&loghandle->u.phd.phd_entry);
+        if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_CAT)
+                LASSERT(list_empty(&loghandle->u.chd.chd_head));
+        OBD_FREE(loghandle->lgh_hdr, LLOG_CHUNK_SIZE);
+
+ out:
+        OBD_FREE(loghandle, sizeof(*loghandle));
+}
+EXPORT_SYMBOL(llog_free_handle);
+
+/* returns negative on error; 0 if success; 1 if success & log destroyed */
+int llog_cancel_rec(struct llog_handle *loghandle, int index)
+{
+        struct llog_log_hdr *llh = loghandle->lgh_hdr;
+        int rc = 0;
+        ENTRY;
+
+        CDEBUG(D_HA, "canceling %d in log "LPX64"\n",
+               index, loghandle->lgh_id.lgl_oid);
+
+        if (index == 0) {
+                CERROR("cannot cancel index 0 (which is header)\n");
+                RETURN(-EINVAL);
+        }
+
+        if (!ext2_clear_bit(index, llh->llh_bitmap)) {
+                CERROR("catalog index %u already clear?\n", index);
+                RETURN(-EINVAL);
+        }
+
+        llh->llh_count--;
+
+        if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
+            (llh->llh_count == 1) &&
+            (loghandle->lgh_last_idx == (LLOG_BITMAP_BYTES * 8) - 1)) {
+                rc = llog_destroy(loghandle);
+                if (rc)
+                        CERROR("failure destroying log after last cancel: %d\n",
+                               rc);
+                LASSERT(rc == 0);
+                RETURN(1);
+        }
+
+        rc = llog_write_rec(loghandle, &llh->llh_hdr, NULL, 0, NULL, 0);
+        if (rc)
+                CERROR("failure re-writing header %d\n", rc);
+        LASSERT(rc == 0);
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cancel_rec);
+
+int llog_init_handle(struct llog_handle *handle, int flags,
+                     struct obd_uuid *uuid)
+{
+        int rc;
+        struct llog_log_hdr *llh;
+        ENTRY;
+        LASSERT(handle->lgh_hdr == NULL);
+
+        OBD_ALLOC(llh, sizeof(*llh));
+        if (llh == NULL)
+                RETURN(-ENOMEM);
+        handle->lgh_hdr = llh;
+        /* first assign flags to use llog_client_ops */
+        llh->llh_flags = flags;
+        rc = llog_read_header(handle);
+        if (rc == 0) {
+                flags = llh->llh_flags;
+                if (uuid)
+                        LASSERT(obd_uuid_equals(uuid, &llh->llh_tgtuuid));
+                GOTO(out, rc);
+        } else if (rc != LLOG_EEMPTY || !flags) {
+                /* set a pesudo flag for initialization */
+                flags = LLOG_F_IS_CAT;
+                GOTO(out, rc);
+        }
+        rc = 0;
+
+        handle->lgh_last_idx = 0; /* header is record with index 0 */
+        llh->llh_count = 1;         /* for the header record */
+        llh->llh_hdr.lrh_type = LLOG_HDR_MAGIC;
+        llh->llh_hdr.lrh_len = llh->llh_tail.lrt_len = LLOG_CHUNK_SIZE;
+        llh->llh_hdr.lrh_index = llh->llh_tail.lrt_index = 0;
+        llh->llh_timestamp = LTIME_S(CURRENT_TIME);
+        if (uuid)
+                memcpy(&llh->llh_tgtuuid, uuid, sizeof(llh->llh_tgtuuid));
+        llh->llh_bitmap_offset = offsetof(typeof(*llh),llh_bitmap);
+        ext2_set_bit(0, llh->llh_bitmap);
+
+out:
+        if (flags & LLOG_F_IS_CAT) {
+                INIT_LIST_HEAD(&handle->u.chd.chd_head);
+                llh->llh_size = sizeof(struct llog_logid_rec);
+        }
+        else if (flags & LLOG_F_IS_PLAIN)
+                INIT_LIST_HEAD(&handle->u.phd.phd_entry);
+        else
+                LBUG();
+
+        if (rc) {
+                OBD_FREE(llh, sizeof(*llh));
+                handle->lgh_hdr = NULL;
+        }
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_init_handle);
+
+int llog_close(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, -EOPNOTSUPP);
+        rc = lop->lop_close(loghandle);
+ out:
+        llog_free_handle(loghandle);
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_close);
+
+int llog_process(struct llog_handle *loghandle, llog_cb_t cb,
+                 void *data, void *catdata)
+{
+        struct llog_log_hdr *llh = loghandle->lgh_hdr;
+        struct llog_process_cat_data *cd = catdata;
+        void *buf;
+        __u64 cur_offset = LLOG_CHUNK_SIZE;
+        int rc = 0, index = 1, last_index, idx;
+        int saved_index = 0;
+        ENTRY;
+
+        OBD_ALLOC(buf, LLOG_CHUNK_SIZE);
+        if (!buf)
+                RETURN(-ENOMEM);
+
+        if (cd != NULL)
+                index = cd->first_idx + 1;
+        if (cd != NULL && cd->last_idx)
+                last_index = cd->last_idx;
+        else
+                last_index = LLOG_BITMAP_BYTES * 8 - 1;
+
+        while (rc == 0) {
+                struct llog_rec_hdr *rec;
+
+                /* skip records not set in bitmap */
+                while (index <= last_index &&
+                       !ext2_test_bit(index, llh->llh_bitmap))
+                        ++index;
+
+                LASSERT(index <= last_index + 1);
+                if (index == last_index + 1)
+                        break;
+
+                /* get the buf with our target record; avoid old garbage */
+                memset(buf, 0, LLOG_CHUNK_SIZE);
+                rc = llog_next_block(loghandle, &saved_index, index,
+                                     &cur_offset, buf, LLOG_CHUNK_SIZE);
+                if (rc)
+                        GOTO(out, rc);
+
+                rec = buf;
+                idx = rec->lrh_index;
+                if (idx < index)
+                        CDEBUG(D_HA, "index %u : idx %u\n", index, idx);
+                while (idx < index) {
+                        rec = (struct llog_rec_hdr *)
+                                ((char *)rec + rec->lrh_len);
+                        idx ++;
+                }
+
+                /* process records in buffer, starting where we found one */
+                while ((void *)rec < buf + LLOG_CHUNK_SIZE) {
+                        if (rec->lrh_index == 0)
+                                GOTO(out, 0); /* no more records */
+
+                        /* if set, process the callback on this record */
+                        if (ext2_test_bit(index, llh->llh_bitmap)) {
+                                rc = cb(loghandle, rec, data);
+                                if (rc == LLOG_PROC_BREAK) {
+                                        CWARN("recovery from log: "LPX64":%x"
+                                              " stopped\n",
+                                              loghandle->lgh_id.lgl_oid,
+                                              loghandle->lgh_id.lgl_ogen);
+                                        GOTO(out, rc);
+                                }
+                                if (rc)
+                                        GOTO(out, rc);
+                        }
+
+                        /* next record, still in buffer? */
+                        ++index;
+                        if (index > last_index)
+                                GOTO(out, rc = 0);
+                        rec = (struct llog_rec_hdr *)
+                                ((char *)rec + rec->lrh_len);
+                }
+        }
+
+ out:
+        if (buf)
+                OBD_FREE(buf, LLOG_CHUNK_SIZE);
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_process);

lustre/obdclass/llog_cat.c

+/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
+ * vim:expandtab:shiftwidth=8:tabstop=8:
+ *
+ *  Copyright (C) 2001-2003 Cluster File Systems, Inc.
+ *   Author: Andreas Dilger <adilger@clusterfs.com>
+ *
+ *   This file is part of Lustre, http://www.lustre.org.
+ *
+ *   Lustre is free software; you can redistribute it and/or
+ *   modify it under the terms of version 2 of the GNU General Public
+ *   License as published by the Free Software Foundation.
+ *
+ *   Lustre is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with Lustre; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * OST<->MDS recovery logging infrastructure.
+ *
+ * Invariants in implementation:
+ * - we do not share logs among different OST<->MDS connections, so that
+ *   if an OST or MDS fails it need only look at log(s) relevant to itself
+ */
+
+#define DEBUG_SUBSYSTEM S_LOG
+
+#ifndef EXPORT_SYMTAB
+#define EXPORT_SYMTAB
+#endif
+
+#ifdef __KERNEL__
+#include <linux/fs.h>
+#else
+#include <liblustre.h>
+#endif
+
+#include <linux/obd_class.h>
+#include <linux/lustre_log.h>
+#include <portals/list.h>
+
+/* 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.
+ *
+ * Assumes caller has already pushed us into the kernel context and is locking.
+ */
+static struct llog_handle *llog_cat_new_log(struct llog_handle *cathandle)
+{
+        struct llog_handle *loghandle;
+        struct llog_log_hdr *llh;
+        struct llog_logid_rec rec = { { 0 }, };
+        int rc, index, bitmap_size;
+        ENTRY;
+
+        llh = cathandle->lgh_hdr;
+        bitmap_size = sizeof(llh->llh_bitmap) * 8;
+
+        index = (cathandle->lgh_last_idx + 1) % bitmap_size;
+
+        /* maximum number of available slots in catlog is bitmap_size - 2 */
+        if (llh->llh_cat_idx == index) {
+                CERROR("no free catalog slots for log...\n");
+                RETURN(ERR_PTR(-ENOSPC));
+        } else {
+                if (index == 0)
+                        index = 1;
+                if (ext2_set_bit(index, llh->llh_bitmap)) {
+                        CERROR("argh, index %u already set in log bitmap?\n",
+                               index);
+                        LBUG(); /* should never happen */
+                }
+                cathandle->lgh_last_idx = index;
+                llh->llh_count++;
+                llh->llh_tail.lrt_index = index;
+        }
+
+        rc = llog_create(cathandle->lgh_ctxt, &loghandle, NULL, NULL);
+        if (rc)
+                RETURN(ERR_PTR(rc));
+
+        rc = llog_init_handle(loghandle,
+                              LLOG_F_IS_PLAIN | LLOG_F_ZAP_WHEN_EMPTY,
+                              &cathandle->lgh_hdr->llh_tgtuuid);
+        if (rc)
+                GOTO(out_destroy, rc);
+
+        CDEBUG(D_HA, "new recovery log "LPX64":%x for index %u of catalog "
+               LPX64"\n", loghandle->lgh_id.lgl_oid, loghandle->lgh_id.lgl_ogen,
+               index, cathandle->lgh_id.lgl_oid);
+        /* build the record for this log in the catalog */
+        rec.lid_hdr.lrh_len = sizeof(rec);
+        rec.lid_hdr.lrh_index = index;
+        rec.lid_hdr.lrh_type = LLOG_LOGID_MAGIC;
+        rec.lid_id = loghandle->lgh_id;
+        rec.lid_tail.lrt_len = sizeof(rec);
+        rec.lid_tail.lrt_index = index;
+
+        /* update the catalog: header and record */
+        rc = llog_write_rec(cathandle, &rec.lid_hdr,
+                            &loghandle->u.phd.phd_cookie, 1, NULL, index);
+        if (rc < 0) {
+                GOTO(out_destroy, rc);
+        }
+
+        loghandle->lgh_hdr->llh_cat_idx = index;
+        cathandle->u.chd.chd_current_log = loghandle;
+        LASSERT(list_empty(&loghandle->u.phd.phd_entry));
+        list_add_tail(&loghandle->u.phd.phd_entry, &cathandle->u.chd.chd_head);
+
+ out_destroy:
+        if (rc < 0)
+                llog_destroy(loghandle);
+
+        RETURN(loghandle);
+}
+EXPORT_SYMBOL(llog_cat_new_log);
+
+/* 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.
+ *
+ * Assumes caller has already pushed us into the kernel context and is locking.
+ * We return a lock on the handle to ensure nobody yanks it from us.
+ */
+int llog_cat_id2handle(struct llog_handle *cathandle, struct llog_handle **res,
+                       struct llog_logid *logid)
+{
+        struct llog_handle *loghandle;
+        int rc = 0;
+        ENTRY;
+
+        if (cathandle == NULL)
+                RETURN(-EBADF);
+
+        list_for_each_entry(loghandle, &cathandle->u.chd.chd_head,
+                            u.phd.phd_entry) {
+                struct llog_logid *cgl = &loghandle->lgh_id;
+                if (cgl->lgl_oid == logid->lgl_oid) {
+                        if (cgl->lgl_ogen != logid->lgl_ogen) {
+                                CERROR("log "LPX64" generation %x != %x\n",
+                                       logid->lgl_oid, cgl->lgl_ogen,
+                                       logid->lgl_ogen);
+                                continue;
+                        }
+                        loghandle->u.phd.phd_cat_handle = cathandle;
+                        GOTO(out, rc = 0);
+                }
+        }
+
+        rc = llog_create(cathandle->lgh_ctxt, &loghandle, logid, NULL);
+        if (rc) {
+                CERROR("error opening log id "LPX64":%x: rc %d\n",
+                       logid->lgl_oid, logid->lgl_ogen, rc);
+        } else {
+                rc = llog_init_handle(loghandle, LLOG_F_IS_PLAIN, NULL);
+                if (!rc) {
+                        list_add(&loghandle->u.phd.phd_entry,
+                                 &cathandle->u.chd.chd_head);
+                }
+        }
+        if (!rc) {
+                loghandle->u.phd.phd_cat_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;
+        }
+
+out:
+        *res = loghandle;
+        RETURN(rc);
+}
+
+int llog_cat_put(struct llog_handle *cathandle)
+{
+        struct llog_handle *loghandle, *n;
+        int rc;
+        ENTRY;
+
+        list_for_each_entry_safe(loghandle, n, &cathandle->u.chd.chd_head,
+                                 u.phd.phd_entry) {
+                int err = llog_close(loghandle);
+                if (err)
+                        CERROR("error closing loghandle\n");
+        }
+        rc = llog_close(cathandle);
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_put);
+
+/* 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.
+ *
+ * If reclen is 0, we only want to know what the currently active log is,
+ * otherwise we get a lock on this log so nobody can steal our space.
+ *
+ * Assumes caller has already pushed us into the kernel context and is locking.
+ *
+ * NOTE: loghandle is write-locked upon successful return
+ */
+static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
+                                                int create)
+{
+        struct llog_handle *loghandle = NULL;
+        ENTRY;
+
+        down_read(&cathandle->lgh_lock);
+        loghandle = cathandle->u.chd.chd_current_log;
+        if (loghandle) {
+                struct llog_log_hdr *llh = loghandle->lgh_hdr;
+                if (loghandle->lgh_last_idx < (sizeof(llh->llh_bitmap)*8) - 1) {
+                        down_write(&loghandle->lgh_lock);
+                        up_read(&cathandle->lgh_lock);
+                        RETURN(loghandle);
+                }
+        }
+        if (!create) {
+                if (loghandle)
+                        down_write(&loghandle->lgh_lock);
+                up_read(&cathandle->lgh_lock);
+                RETURN(loghandle);
+        }
+        up_read(&cathandle->lgh_lock);
+
+        /* time to create new log */
+
+        /* first, we have to make sure the state hasn't changed */
+        down_write(&cathandle->lgh_lock);
+        loghandle = cathandle->u.chd.chd_current_log;
+        if (loghandle) {
+                struct llog_log_hdr *llh = loghandle->lgh_hdr;
+                if (loghandle->lgh_last_idx < (sizeof(llh->llh_bitmap)*8) - 1) {
+                        down_write(&loghandle->lgh_lock);
+                        up_write(&cathandle->lgh_lock);
+                        RETURN(loghandle);
+                }
+        }
+
+        CDEBUG(D_INODE, "creating new log\n");
+        loghandle = llog_cat_new_log(cathandle);
+        if (!IS_ERR(loghandle))
+                down_write(&loghandle->lgh_lock);
+        up_write(&cathandle->lgh_lock);
+        RETURN(loghandle);
+}
+
+/* Add a single record to the recovery log(s) using a catalog
+ * Returns as llog_write_record
+ *
+ * Assumes caller has already pushed us into the kernel context.
+ */
+int llog_cat_add_rec(struct llog_handle *cathandle, struct llog_rec_hdr *rec,
+                     struct llog_cookie *reccookie, void *buf)
+{
+        struct llog_handle *loghandle;
+        int rc;
+        ENTRY;
+
+        LASSERT(rec->lrh_len <= LLOG_CHUNK_SIZE);
+        loghandle = llog_cat_current_log(cathandle, 1);
+        if (IS_ERR(loghandle))
+                RETURN(PTR_ERR(loghandle));
+        /* loghandle is already locked by llog_cat_current_log() for us */
+        rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
+        up_write(&loghandle->lgh_lock);
+        if (rc == -ENOSPC) {
+                /* to create a new plain log */
+                loghandle = llog_cat_current_log(cathandle, 1);
+                if (IS_ERR(loghandle))
+                        RETURN(PTR_ERR(loghandle));
+                rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
+                up_write(&loghandle->lgh_lock);
+        }
+
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_add_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
+ *
+ * The cookies may be in different log files, so we need to get new logs
+ * each time.
+ *
+ * Assumes caller has already pushed us into the kernel context.
+ */
+int llog_cat_cancel_records(struct llog_handle *cathandle, int count,
+                        struct llog_cookie *cookies)
+{
+        int i, index, rc = 0;
+        ENTRY;
+
+        down_write(&cathandle->lgh_lock);
+        for (i = 0; i < count; i++, cookies++) {
+                struct llog_handle *loghandle;
+                struct llog_logid *lgl = &cookies->lgc_lgl;
+
+                rc = llog_cat_id2handle(cathandle, &loghandle, lgl);
+                if (rc) {
+                        CERROR("Cannot find log "LPX64"\n", lgl->lgl_oid);
+                        break;
+                }
+
+                down_write(&loghandle->lgh_lock);
+                rc = llog_cancel_rec(loghandle, cookies->lgc_index);
+                up_write(&loghandle->lgh_lock);
+
+                if (rc == 1) {          /* log has been destroyed */
+                        index = loghandle->u.phd.phd_cookie.lgc_index;
+                        if (cathandle->u.chd.chd_current_log == loghandle)
+                                cathandle->u.chd.chd_current_log = NULL;
+                        llog_free_handle(loghandle);
+
+                        LASSERT(index);
+                        llog_cat_set_first_idx(cathandle, index);
+                        rc = llog_cancel_rec(cathandle, index);
+                        if (rc == 0)
+                                CDEBUG(D_HA, "cancel plain log at index %u "
+                                       "of catalog "LPX64"\n",
+                                       index, cathandle->lgh_id.lgl_oid);
+                }
+        }
+        up_write(&cathandle->lgh_lock);
+
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_cancel_records);
+
+int llog_cat_process_cb(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;
+        int rc;
+
+        if (rec->lrh_type != LLOG_LOGID_MAGIC) {
+                CERROR("invalid record in catalog\n");
+                RETURN(-EINVAL);
+        }
+        CWARN("processing log "LPX64":%x at index %u of catalog "LPX64"\n",
+               lir->lid_id.lgl_oid, lir->lid_id.lgl_ogen,
+               rec->lrh_index, cat_llh->lgh_id.lgl_oid);
+
+        rc = llog_cat_id2handle(cat_llh, &llh, &lir->lid_id);
+        if (rc) {
+                CERROR("Cannot find handle for log "LPX64"\n",
+                       lir->lid_id.lgl_oid);
+                RETURN(rc);
+        }
+
+        rc = llog_process(llh, d->lpd_cb, d->lpd_data, NULL);
+        RETURN(rc);
+}
+
+int llog_cat_process(struct llog_handle *cat_llh, llog_cb_t cb, void *data)
+{
+        struct llog_process_data d;
+        struct llog_process_cat_data cd;
+        struct llog_log_hdr *llh = cat_llh->lgh_hdr;
+        int rc;
+        ENTRY;
+
+        LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
+        d.lpd_data = data;
+        d.lpd_cb = cb;
+
+        if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
+                CWARN("catlog "LPX64" crosses index zero\n",
+                      cat_llh->lgh_id.lgl_oid);
+
+                cd.first_idx = llh->llh_cat_idx;
+                cd.last_idx = 0;
+                rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
+                if (rc != 0)
+                        RETURN(rc);
+
+                cd.first_idx = 0;
+                cd.last_idx = cat_llh->lgh_last_idx;
+                rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
+        } else {
+                rc = llog_process(cat_llh, llog_cat_process_cb, &d, NULL);
+        }
+
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_process);
+
+int llog_cat_set_first_idx(struct llog_handle *cathandle, int index)
+{
+        struct llog_log_hdr *llh = cathandle->lgh_hdr;
+        int i, bitmap_size, idx;
+        ENTRY;
+
+        bitmap_size = sizeof(llh->llh_bitmap) * 8;
+        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_HA, "set catlog "LPX64" first idx %u\n",
+                       cathandle->lgh_id.lgl_oid, llh->llh_cat_idx);
+        }
+
+        RETURN(0);
+}
+
+#if 0
+/* Assumes caller has already pushed us into the kernel context. */
+int llog_cat_init(struct llog_handle *cathandle, struct obd_uuid *tgtuuid)
+{
+        struct llog_log_hdr *llh;
+        loff_t offset = 0;
+        int rc = 0;
+        ENTRY;
+
+        LASSERT(sizeof(*llh) == LLOG_CHUNK_SIZE);
+
+        down(&cathandle->lgh_lock);
+        llh = cathandle->lgh_hdr;
+
+        if (cathandle->lgh_file->f_dentry->d_inode->i_size == 0) {
+                llog_write_rec(cathandle, &llh->llh_hdr, NULL, 0, NULL, 0);
+
+write_hdr:
+                rc = lustre_fwrite(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
+                                   &offset);
+                if (rc != LLOG_CHUNK_SIZE) {
+                        CERROR("error writing catalog header: rc %d\n", rc);
+                        OBD_FREE(llh, sizeof(*llh));
+                        if (rc >= 0)
+                                rc = -ENOSPC;
+                } else
+                        rc = 0;
+        } else {
+                rc = lustre_fread(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
+                                  &offset);
+                if (rc != LLOG_CHUNK_SIZE) {
+                        CERROR("error reading catalog header: rc %d\n", rc);
+                        /* Can we do much else if the header is bad? */
+                        goto write_hdr;
+                } else
+                        rc = 0;
+        }
+
+        cathandle->lgh_tgtuuid = &llh->llh_tgtuuid;
+        up(&cathandle->lgh_lock);
+        RETURN(rc);
+}
+EXPORT_SYMBOL(llog_cat_init);
+
+#endif

lustre/obdclass/llog_internal.h

+#ifndef __LLOG_INTERNAL_H__
+#define __LLOG_INTERNAL_H__
+
+int llog_put_cat_list(struct obd_device *obd, struct obd_device *disk_obd,
+                      char *name, int count, struct llog_catid *idarray);
+int llog_cat_id2handle(struct llog_handle *cathandle, struct llog_handle **res,
+                       struct llog_logid *logid);
+#endif