/* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU General Public License version 2. */ #include #include #include #include #include #include #include #include #include "gfs2.h" #include "incore.h" #include "inode.h" #include "glock.h" #include "log.h" #include "lops.h" #include "meta_io.h" #include "recovery.h" #include "rgrp.h" #include "trans.h" #include "util.h" #include "trace_gfs2.h" /** * gfs2_pin - Pin a buffer in memory * @sdp: The superblock * @bh: The buffer to be pinned * * The log lock must be held when calling this function */ static void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh) { struct gfs2_bufdata *bd; BUG_ON(!current->journal_info); clear_buffer_dirty(bh); if (test_set_buffer_pinned(bh)) gfs2_assert_withdraw(sdp, 0); if (!buffer_uptodate(bh)) gfs2_io_error_bh(sdp, bh); bd = bh->b_private; /* If this buffer is in the AIL and it has already been written * to in-place disk block, remove it from the AIL. */ spin_lock(&sdp->sd_ail_lock); if (bd->bd_ail) list_move(&bd->bd_ail_st_list, &bd->bd_ail->ai_ail2_list); spin_unlock(&sdp->sd_ail_lock); get_bh(bh); atomic_inc(&sdp->sd_log_pinned); trace_gfs2_pin(bd, 1); } static bool buffer_is_rgrp(const struct gfs2_bufdata *bd) { return bd->bd_gl->gl_name.ln_type == LM_TYPE_RGRP; } static void maybe_release_space(struct gfs2_bufdata *bd) { struct gfs2_glock *gl = bd->bd_gl; struct gfs2_sbd *sdp = gl->gl_sbd; struct gfs2_rgrpd *rgd = gl->gl_object; unsigned int index = bd->bd_bh->b_blocknr - gl->gl_name.ln_number; struct gfs2_bitmap *bi = rgd->rd_bits + index; if (bi->bi_clone == 0) return; if (sdp->sd_args.ar_discard) gfs2_rgrp_send_discards(sdp, rgd->rd_data0, bd->bd_bh, bi); memcpy(bi->bi_clone + bi->bi_offset, bd->bd_bh->b_data + bi->bi_offset, bi->bi_len); clear_bit(GBF_FULL, &bi->bi_flags); rgd->rd_free_clone = rgd->rd_free; } /** * gfs2_unpin - Unpin a buffer * @sdp: the filesystem the buffer belongs to * @bh: The buffer to unpin * @ai: * @flags: The inode dirty flags * */ static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh, struct gfs2_ail *ai) { struct gfs2_bufdata *bd = bh->b_private; BUG_ON(!buffer_uptodate(bh)); BUG_ON(!buffer_pinned(bh)); lock_buffer(bh); mark_buffer_dirty(bh); clear_buffer_pinned(bh); if (buffer_is_rgrp(bd)) maybe_release_space(bd); spin_lock(&sdp->sd_ail_lock); if (bd->bd_ail) { list_del(&bd->bd_ail_st_list); brelse(bh); } else { struct gfs2_glock *gl = bd->bd_gl; list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list); atomic_inc(&gl->gl_ail_count); } bd->bd_ail = ai; list_add(&bd->bd_ail_st_list, &ai->ai_ail1_list); spin_unlock(&sdp->sd_ail_lock); clear_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags); trace_gfs2_pin(bd, 0); unlock_buffer(bh); atomic_dec(&sdp->sd_log_pinned); } static inline struct gfs2_log_descriptor *bh_log_desc(struct buffer_head *bh) { return (struct gfs2_log_descriptor *)bh->b_data; } static inline __be64 *bh_log_ptr(struct buffer_head *bh) { struct gfs2_log_descriptor *ld = bh_log_desc(bh); return (__force __be64 *)(ld + 1); } static inline __be64 *bh_ptr_end(struct buffer_head *bh) { return (__force __be64 *)(bh->b_data + bh->b_size); } static struct buffer_head *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type) { struct buffer_head *bh = gfs2_log_get_buf(sdp); struct gfs2_log_descriptor *ld = bh_log_desc(bh); ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC); ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD); ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD); ld->ld_type = cpu_to_be32(ld_type); ld->ld_length = 0; ld->ld_data1 = 0; ld->ld_data2 = 0; memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved)); return bh; } static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) { struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le); struct gfs2_meta_header *mh; struct gfs2_trans *tr; lock_buffer(bd->bd_bh); gfs2_log_lock(sdp); if (!list_empty(&bd->bd_list_tr)) goto out; tr = current->journal_info; tr->tr_touched = 1; tr->tr_num_buf++; list_add(&bd->bd_list_tr, &tr->tr_list_buf); if (!list_empty(&le->le_list)) goto out; set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags); set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags); gfs2_meta_check(sdp, bd->bd_bh); gfs2_pin(sdp, bd->bd_bh); mh = (struct gfs2_meta_header *)bd->bd_bh->b_data; mh->__pad0 = cpu_to_be64(0); mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); sdp->sd_log_num_buf++; list_add(&le->le_list, &sdp->sd_log_le_buf); tr->tr_num_buf_new++; out: gfs2_log_unlock(sdp); unlock_buffer(bd->bd_bh); } static void buf_lo_before_commit(struct gfs2_sbd *sdp) { struct buffer_head *bh; struct gfs2_log_descriptor *ld; struct gfs2_bufdata *bd1 = NULL, *bd2; unsigned int total; unsigned int limit; unsigned int num; unsigned n; __be64 *ptr; limit = buf_limit(sdp); /* for 4k blocks, limit = 503 */ gfs2_log_lock(sdp); total = sdp->sd_log_num_buf; bd1 = bd2 = list_prepare_entry(bd1, &sdp->sd_log_le_buf, bd_le.le_list); while(total) { num = total; if (total > limit) num = limit; gfs2_log_unlock(sdp); bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_METADATA); gfs2_log_lock(sdp); ld = bh_log_desc(bh); ptr = bh_log_ptr(bh); ld->ld_length = cpu_to_be32(num + 1); ld->ld_data1 = cpu_to_be32(num); n = 0; list_for_each_entry_continue(bd1, &sdp->sd_log_le_buf, bd_le.le_list) { *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr); if (++n >= num) break; } gfs2_log_unlock(sdp); submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); n = 0; list_for_each_entry_continue(bd2, &sdp->sd_log_le_buf, bd_le.le_list) { get_bh(bd2->bd_bh); gfs2_log_unlock(sdp); lock_buffer(bd2->bd_bh); bh = gfs2_log_fake_buf(sdp, bd2->bd_bh); submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); if (++n >= num) break; } BUG_ON(total < num); total -= num; } gfs2_log_unlock(sdp); } static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai) { struct list_head *head = &sdp->sd_log_le_buf; struct gfs2_bufdata *bd; while (!list_empty(head)) { bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list); list_del_init(&bd->bd_le.le_list); sdp->sd_log_num_buf--; gfs2_unpin(sdp, bd->bd_bh, ai); } gfs2_assert_warn(sdp, !sdp->sd_log_num_buf); } static void buf_lo_before_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head, int pass) { struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); if (pass != 0) return; sdp->sd_found_blocks = 0; sdp->sd_replayed_blocks = 0; } static int buf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start, struct gfs2_log_descriptor *ld, __be64 *ptr, int pass) { struct gfs2_inode *ip = GFS2_I(jd->jd_inode); struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); struct gfs2_glock *gl = ip->i_gl; unsigned int blks = be32_to_cpu(ld->ld_data1); struct buffer_head *bh_log, *bh_ip; u64 blkno; int error = 0; if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_METADATA) return 0; gfs2_replay_incr_blk(sdp, &start); for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) { blkno = be64_to_cpu(*ptr++); sdp->sd_found_blocks++; if (gfs2_revoke_check(sdp, blkno, start)) continue; error = gfs2_replay_read_block(jd, start, &bh_log); if (error) return error; bh_ip = gfs2_meta_new(gl, blkno); memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size); if (gfs2_meta_check(sdp, bh_ip)) error = -EIO; else mark_buffer_dirty(bh_ip); brelse(bh_log); brelse(bh_ip); if (error) break; sdp->sd_replayed_blocks++; } return error; } static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass) { struct gfs2_inode *ip = GFS2_I(jd->jd_inode); struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); if (error) { gfs2_meta_sync(ip->i_gl); return; } if (pass != 1) return; gfs2_meta_sync(ip->i_gl); fs_info(sdp, "jid=%u: Replayed %u of %u blocks\n", jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks); } static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) { struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le); struct gfs2_glock *gl = bd->bd_gl; struct gfs2_trans *tr; tr = current->journal_info; tr->tr_touched = 1; tr->tr_num_revoke++; sdp->sd_log_num_revoke++; atomic_inc(&gl->gl_revokes); set_bit(GLF_LFLUSH, &gl->gl_flags); list_add(&le->le_list, &sdp->sd_log_le_revoke); } static void revoke_lo_before_commit(struct gfs2_sbd *sdp) { struct gfs2_log_descriptor *ld; struct gfs2_meta_header *mh; struct buffer_head *bh; unsigned int offset; struct list_head *head = &sdp->sd_log_le_revoke; struct gfs2_bufdata *bd; if (!sdp->sd_log_num_revoke) return; bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_REVOKE); ld = bh_log_desc(bh); ld->ld_length = cpu_to_be32(gfs2_struct2blk(sdp, sdp->sd_log_num_revoke, sizeof(u64))); ld->ld_data1 = cpu_to_be32(sdp->sd_log_num_revoke); offset = sizeof(struct gfs2_log_descriptor); list_for_each_entry(bd, head, bd_le.le_list) { sdp->sd_log_num_revoke--; if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) { submit_bh(WRITE_SYNC, bh); bh = gfs2_log_get_buf(sdp); mh = (struct gfs2_meta_header *)bh->b_data; mh->mh_magic = cpu_to_be32(GFS2_MAGIC); mh->mh_type = cpu_to_be32(GFS2_METATYPE_LB); mh->mh_format = cpu_to_be32(GFS2_FORMAT_LB); offset = sizeof(struct gfs2_meta_header); } *(__be64 *)(bh->b_data + offset) = cpu_to_be64(bd->bd_blkno); offset += sizeof(u64); } gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); submit_bh(WRITE_SYNC, bh); } static void revoke_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai) { struct list_head *head = &sdp->sd_log_le_revoke; struct gfs2_bufdata *bd; struct gfs2_glock *gl; while (!list_empty(head)) { bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list); list_del_init(&bd->bd_le.le_list); gl = bd->bd_gl; atomic_dec(&gl->gl_revokes); clear_bit(GLF_LFLUSH, &gl->gl_flags); kmem_cache_free(gfs2_bufdata_cachep, bd); } } static void revoke_lo_before_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head, int pass) { struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); if (pass != 0) return; sdp->sd_found_revokes = 0; sdp->sd_replay_tail = head->lh_tail; } static int revoke_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start, struct gfs2_log_descriptor *ld, __be64 *ptr, int pass) { struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); unsigned int blks = be32_to_cpu(ld->ld_length); unsigned int revokes = be32_to_cpu(ld->ld_data1); struct buffer_head *bh; unsigned int offset; u64 blkno; int first = 1; int error; if (pass != 0 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_REVOKE) return 0; offset = sizeof(struct gfs2_log_descriptor); for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) { error = gfs2_replay_read_block(jd, start, &bh); if (error) return error; if (!first) gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LB); while (offset + sizeof(u64) <= sdp->sd_sb.sb_bsize) { blkno = be64_to_cpu(*(__be64 *)(bh->b_data + offset)); error = gfs2_revoke_add(sdp, blkno, start); if (error < 0) { brelse(bh); return error; } else if (error) sdp->sd_found_revokes++; if (!--revokes) break; offset += sizeof(u64); } brelse(bh); offset = sizeof(struct gfs2_meta_header); first = 0; } return 0; } static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass) { struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); if (error) { gfs2_revoke_clean(sdp); return; } if (pass != 1) return; fs_info(sdp, "jid=%u: Found %u revoke tags\n", jd->jd_jid, sdp->sd_found_revokes); gfs2_revoke_clean(sdp); } /** * databuf_lo_add - Add a databuf to the transaction. * * This is used in two distinct cases: * i) In ordered write mode * We put the data buffer on a list so that we can ensure that its * synced to disk at the right time * ii) In journaled data mode * We need to journal the data block in the same way as metadata in * the functions above. The difference is that here we have a tag * which is two __be64's being the block number (as per meta data) * and a flag which says whether the data block needs escaping or * not. This means we need a new log entry for each 251 or so data * blocks, which isn't an enormous overhead but twice as much as * for normal metadata blocks. */ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) { struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le); struct gfs2_trans *tr = current->journal_info; struct address_space *mapping = bd->bd_bh->b_page->mapping; struct gfs2_inode *ip = GFS2_I(mapping->host); lock_buffer(bd->bd_bh); gfs2_log_lock(sdp); if (tr) { if (!list_empty(&bd->bd_list_tr)) goto out; tr->tr_touched = 1; if (gfs2_is_jdata(ip)) { tr->tr_num_buf++; list_add(&bd->bd_list_tr, &tr->tr_list_buf); } } if (!list_empty(&le->le_list)) goto out; set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags); set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags); if (gfs2_is_jdata(ip)) { gfs2_pin(sdp, bd->bd_bh); tr->tr_num_databuf_new++; sdp->sd_log_num_databuf++; list_add_tail(&le->le_list, &sdp->sd_log_le_databuf); } else { list_add_tail(&le->le_list, &sdp->sd_log_le_ordered); } out: gfs2_log_unlock(sdp); unlock_buffer(bd->bd_bh); } static void gfs2_check_magic(struct buffer_head *bh) { void *kaddr; __be32 *ptr; clear_buffer_escaped(bh); kaddr = kmap_atomic(bh->b_page, KM_USER0); ptr = kaddr + bh_offset(bh); if (*ptr == cpu_to_be32(GFS2_MAGIC)) set_buffer_escaped(bh); kunmap_atomic(kaddr, KM_USER0); } static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh, struct list_head *list, struct list_head *done, unsigned int n) { struct buffer_head *bh1; struct gfs2_log_descriptor *ld; struct gfs2_bufdata *bd; __be64 *ptr; if (!bh) return; ld = bh_log_desc(bh); ld->ld_length = cpu_to_be32(n + 1); ld->ld_data1 = cpu_to_be32(n); ptr = bh_log_ptr(bh); get_bh(bh); submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); while(!list_empty(list)) { bd = list_entry(list->next, struct gfs2_bufdata, bd_le.le_list); list_move_tail(&bd->bd_le.le_list, done); get_bh(bd->bd_bh); while (be64_to_cpu(*ptr) != bd->bd_bh->b_blocknr) { gfs2_log_incr_head(sdp); ptr += 2; } gfs2_log_unlock(sdp); lock_buffer(bd->bd_bh); if (buffer_escaped(bd->bd_bh)) { void *kaddr; bh1 = gfs2_log_get_buf(sdp); kaddr = kmap_atomic(bd->bd_bh->b_page, KM_USER0); memcpy(bh1->b_data, kaddr + bh_offset(bd->bd_bh), bh1->b_size); kunmap_atomic(kaddr, KM_USER0); *(__be32 *)bh1->b_data = 0; clear_buffer_escaped(bd->bd_bh); unlock_buffer(bd->bd_bh); brelse(bd->bd_bh); } else { bh1 = gfs2_log_fake_buf(sdp, bd->bd_bh); } submit_bh(WRITE_SYNC, bh1); gfs2_log_lock(sdp); ptr += 2; } gfs2_log_unlock(sdp); brelse(bh); } /** * databuf_lo_before_commit - Scan the data buffers, writing as we go * */ static void databuf_lo_before_commit(struct gfs2_sbd *sdp) { struct gfs2_bufdata *bd = NULL; struct buffer_head *bh = NULL; unsigned int n = 0; __be64 *ptr = NULL, *end = NULL; LIST_HEAD(processed); LIST_HEAD(in_progress); gfs2_log_lock(sdp); while (!list_empty(&sdp->sd_log_le_databuf)) { if (ptr == end) { gfs2_log_unlock(sdp); gfs2_write_blocks(sdp, bh, &in_progress, &processed, n); n = 0; bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_JDATA); ptr = bh_log_ptr(bh); end = bh_ptr_end(bh) - 1; gfs2_log_lock(sdp); continue; } bd = list_entry(sdp->sd_log_le_databuf.next, struct gfs2_bufdata, bd_le.le_list); list_move_tail(&bd->bd_le.le_list, &in_progress); gfs2_check_magic(bd->bd_bh); *ptr++ = cpu_to_be64(bd->bd_bh->b_blocknr); *ptr++ = cpu_to_be64(buffer_escaped(bh) ? 1 : 0); n++; } gfs2_log_unlock(sdp); gfs2_write_blocks(sdp, bh, &in_progress, &processed, n); gfs2_log_lock(sdp); list_splice(&processed, &sdp->sd_log_le_databuf); gfs2_log_unlock(sdp); } static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start, struct gfs2_log_descriptor *ld, __be64 *ptr, int pass) { struct gfs2_inode *ip = GFS2_I(jd->jd_inode); struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); struct gfs2_glock *gl = ip->i_gl; unsigned int blks = be32_to_cpu(ld->ld_data1); struct buffer_head *bh_log, *bh_ip; u64 blkno; u64 esc; int error = 0; if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA) return 0; gfs2_replay_incr_blk(sdp, &start); for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) { blkno = be64_to_cpu(*ptr++); esc = be64_to_cpu(*ptr++); sdp->sd_found_blocks++; if (gfs2_revoke_check(sdp, blkno, start)) continue; error = gfs2_replay_read_block(jd, start, &bh_log); if (error) return error; bh_ip = gfs2_meta_new(gl, blkno); memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size); /* Unescape */ if (esc) { __be32 *eptr = (__be32 *)bh_ip->b_data; *eptr = cpu_to_be32(GFS2_MAGIC); } mark_buffer_dirty(bh_ip); brelse(bh_log); brelse(bh_ip); if (error) break; sdp->sd_replayed_blocks++; } return error; } /* FIXME: sort out accounting for log blocks etc. */ static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass) { struct gfs2_inode *ip = GFS2_I(jd->jd_inode); struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); if (error) { gfs2_meta_sync(ip->i_gl); return; } if (pass != 1) return; /* data sync? */ gfs2_meta_sync(ip->i_gl); fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n", jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks); } static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai) { struct list_head *head = &sdp->sd_log_le_databuf; struct gfs2_bufdata *bd; while (!list_empty(head)) { bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list); list_del_init(&bd->bd_le.le_list); sdp->sd_log_num_databuf--; gfs2_unpin(sdp, bd->bd_bh, ai); } gfs2_assert_warn(sdp, !sdp->sd_log_num_databuf); } const struct gfs2_log_operations gfs2_buf_lops = { .lo_add = buf_lo_add, .lo_before_commit = buf_lo_before_commit, .lo_after_commit = buf_lo_after_commit, .lo_before_scan = buf_lo_before_scan, .lo_scan_elements = buf_lo_scan_elements, .lo_after_scan = buf_lo_after_scan, .lo_name = "buf", }; const struct gfs2_log_operations gfs2_revoke_lops = { .lo_add = revoke_lo_add, .lo_before_commit = revoke_lo_before_commit, .lo_after_commit = revoke_lo_after_commit, .lo_before_scan = revoke_lo_before_scan, .lo_scan_elements = revoke_lo_scan_elements, .lo_after_scan = revoke_lo_after_scan, .lo_name = "revoke", }; const struct gfs2_log_operations gfs2_rg_lops = { .lo_name = "rg", }; const struct gfs2_log_operations gfs2_databuf_lops = { .lo_add = databuf_lo_add, .lo_before_commit = databuf_lo_before_commit, .lo_after_commit = databuf_lo_after_commit, .lo_scan_elements = databuf_lo_scan_elements, .lo_after_scan = databuf_lo_after_scan, .lo_name = "databuf", }; const struct gfs2_log_operations *gfs2_log_ops[] = { &gfs2_databuf_lops, &gfs2_buf_lops, &gfs2_rg_lops, &gfs2_revoke_lops, NULL, };