[PATCH 1/2] ocfs2: Add group extend for online resize
authorTao Ma <tao.ma@oracle.com>
Tue, 18 Dec 2007 07:47:03 +0000 (15:47 +0800)
committerMark Fasheh <mark.fasheh@oracle.com>
Fri, 25 Jan 2008 22:53:35 +0000 (14:53 -0800)
This patch adds the ability for a userspace program to request an extend of
last cluster group on an Ocfs2 file system. The request is made via ioctl,
OCFS2_IOC_GROUP_EXTEND. This is derived from EXT3_IOC_GROUP_EXTEND, but is
obviously Ocfs2 specific.

tunefs.ocfs2 would call this for an online-resize operation if the last
cluster group isn't full.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
fs/ocfs2/Makefile
fs/ocfs2/buffer_head_io.c
fs/ocfs2/buffer_head_io.h
fs/ocfs2/ioctl.c
fs/ocfs2/journal.h
fs/ocfs2/ocfs2_fs.h
fs/ocfs2/resize.c [new file with mode: 0644]
fs/ocfs2/resize.h [new file with mode: 0644]
fs/ocfs2/suballoc.c
fs/ocfs2/suballoc.h

index d2057e7fbda7a54ac3c3db994b316acda74ea2ba..3591890b32c682df8f73edbeca23cd8741d0dede 100644 (file)
@@ -21,6 +21,7 @@ ocfs2-objs := \
        localalloc.o            \
        mmap.o                  \
        namei.o                 \
+       resize.o                \
        slot_map.o              \
        suballoc.o              \
        super.o                 \
index c9037414f4f65fad9f0b812b9ba75f7c9823cc6d..31aa61dc777bdc8c5c7607075200c8c357e2dae2 100644 (file)
@@ -280,3 +280,64 @@ bail:
        mlog_exit(status);
        return status;
 }
+
+/* Check whether the blkno is the super block or one of the backups. */
+static void ocfs2_check_super_or_backup(struct super_block *sb,
+                                       sector_t blkno)
+{
+       int i;
+       u64 backup_blkno;
+
+       if (blkno == OCFS2_SUPER_BLOCK_BLKNO)
+               return;
+
+       for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
+               backup_blkno = ocfs2_backup_super_blkno(sb, i);
+               if (backup_blkno == blkno)
+                       return;
+       }
+
+       BUG();
+}
+
+/*
+ * Write super block and backups doesn't need to collaborate with journal,
+ * so we don't need to lock ip_io_mutex and inode doesn't need to bea passed
+ * into this function.
+ */
+int ocfs2_write_super_or_backup(struct ocfs2_super *osb,
+                               struct buffer_head *bh)
+{
+       int ret = 0;
+
+       mlog_entry_void();
+
+       BUG_ON(buffer_jbd(bh));
+       ocfs2_check_super_or_backup(osb->sb, bh->b_blocknr);
+
+       if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb)) {
+               ret = -EROFS;
+               goto out;
+       }
+
+       lock_buffer(bh);
+       set_buffer_uptodate(bh);
+
+       /* remove from dirty list before I/O. */
+       clear_buffer_dirty(bh);
+
+       get_bh(bh); /* for end_buffer_write_sync() */
+       bh->b_end_io = end_buffer_write_sync;
+       submit_bh(WRITE, bh);
+
+       wait_on_buffer(bh);
+
+       if (!buffer_uptodate(bh)) {
+               ret = -EIO;
+               brelse(bh);
+       }
+
+out:
+       mlog_exit(ret);
+       return ret;
+}
index 6cc20930fac31429319ce76a060b7475e94f45e9..c2e78614c3e50970ed01521d5e38e2371adeb388 100644 (file)
@@ -47,6 +47,8 @@ int ocfs2_read_blocks(struct ocfs2_super          *osb,
                      int                  flags,
                      struct inode        *inode);
 
+int ocfs2_write_super_or_backup(struct ocfs2_super *osb,
+                               struct buffer_head *bh);
 
 #define OCFS2_BH_CACHED            1
 #define OCFS2_BH_READAHEAD         8
index 67c2fb4bae912b3f63a6b9313f2b623a934521ef..b74b24ecf0e4ba6bfd86d1197954260afca3d6b2 100644 (file)
@@ -20,6 +20,7 @@
 
 #include "ocfs2_fs.h"
 #include "ioctl.h"
+#include "resize.h"
 
 #include <linux/ext2_fs.h>
 
@@ -115,6 +116,7 @@ int ocfs2_ioctl(struct inode * inode, struct file * filp,
        unsigned int cmd, unsigned long arg)
 {
        unsigned int flags;
+       int new_clusters;
        int status;
        struct ocfs2_space_resv sr;
 
@@ -140,6 +142,11 @@ int ocfs2_ioctl(struct inode * inode, struct file * filp,
                        return -EFAULT;
 
                return ocfs2_change_file_space(filp, cmd, &sr);
+       case OCFS2_IOC_GROUP_EXTEND:
+               if (get_user(new_clusters, (int __user *)arg))
+                       return -EFAULT;
+
+               return ocfs2_group_extend(inode, new_clusters);
        default:
                return -ENOTTY;
        }
@@ -162,6 +169,7 @@ long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
        case OCFS2_IOC_RESVSP64:
        case OCFS2_IOC_UNRESVSP:
        case OCFS2_IOC_UNRESVSP64:
+       case OCFS2_IOC_GROUP_EXTEND:
                break;
        default:
                return -ENOIOCTLCMD;
index 4b32e0961568e34372a7ad02c7c8b77b3e0c6c24..0ba3a421ccf2e875cb9a5e1468bff3a4ea5a23f8 100644 (file)
@@ -278,6 +278,9 @@ int                  ocfs2_journal_dirty_data(handle_t *handle,
 /* simple file updates like chmod, etc. */
 #define OCFS2_INODE_UPDATE_CREDITS 1
 
+/* group extend. inode update and last group update. */
+#define OCFS2_GROUP_EXTEND_CREDITS     (OCFS2_INODE_UPDATE_CREDITS + 1)
+
 /* get one bit out of a suballocator: dinode + group descriptor +
  * prev. group desc. if we relink. */
 #define OCFS2_SUBALLOC_ALLOC (3)
index 6ef876759a737eb098d7abbf70e87d69663114f9..19ac421b613b2b42801ded28dd5048c9981136c4 100644 (file)
@@ -231,6 +231,8 @@ struct ocfs2_space_resv {
 #define OCFS2_IOC_RESVSP64     _IOW ('X', 42, struct ocfs2_space_resv)
 #define OCFS2_IOC_UNRESVSP64   _IOW ('X', 43, struct ocfs2_space_resv)
 
+#define OCFS2_IOC_GROUP_EXTEND _IOW('o', 1, int)
+
 /*
  * Journal Flags (ocfs2_dinode.id1.journal1.i_flags)
  */
diff --git a/fs/ocfs2/resize.c b/fs/ocfs2/resize.c
new file mode 100644 (file)
index 0000000..848f729
--- /dev/null
@@ -0,0 +1,398 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * resize.c
+ *
+ * volume resize.
+ * Inspired by ext3/resize.c.
+ *
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+
+#define MLOG_MASK_PREFIX ML_DISK_ALLOC
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "dlmglue.h"
+#include "inode.h"
+#include "journal.h"
+#include "super.h"
+#include "sysfile.h"
+#include "uptodate.h"
+
+#include "buffer_head_io.h"
+#include "suballoc.h"
+#include "resize.h"
+
+/*
+ * Check whether there are new backup superblocks exist
+ * in the last group. If there are some, mark them or clear
+ * them in the bitmap.
+ *
+ * Return how many backups we find in the last group.
+ */
+static u16 ocfs2_calc_new_backup_super(struct inode *inode,
+                                      struct ocfs2_group_desc *gd,
+                                      int new_clusters,
+                                      u32 first_new_cluster,
+                                      u16 cl_cpg,
+                                      int set)
+{
+       int i;
+       u16 backups = 0;
+       u32 cluster;
+       u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno);
+
+       for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
+               blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
+               cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
+
+               gd_blkno = ocfs2_which_cluster_group(inode, cluster);
+               if (gd_blkno < lgd_blkno)
+                       continue;
+               else if (gd_blkno > lgd_blkno)
+                       break;
+
+               if (set)
+                       ocfs2_set_bit(cluster % cl_cpg,
+                                     (unsigned long *)gd->bg_bitmap);
+               else
+                       ocfs2_clear_bit(cluster % cl_cpg,
+                                       (unsigned long *)gd->bg_bitmap);
+               backups++;
+       }
+
+       mlog_exit_void();
+       return backups;
+}
+
+static int ocfs2_update_last_group_and_inode(handle_t *handle,
+                                            struct inode *bm_inode,
+                                            struct buffer_head *bm_bh,
+                                            struct buffer_head *group_bh,
+                                            u32 first_new_cluster,
+                                            int new_clusters)
+{
+       int ret = 0;
+       struct ocfs2_super *osb = OCFS2_SB(bm_inode->i_sb);
+       struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bm_bh->b_data;
+       struct ocfs2_chain_list *cl = &fe->id2.i_chain;
+       struct ocfs2_chain_rec *cr;
+       struct ocfs2_group_desc *group;
+       u16 chain, num_bits, backups = 0;
+       u16 cl_bpc = le16_to_cpu(cl->cl_bpc);
+       u16 cl_cpg = le16_to_cpu(cl->cl_cpg);
+
+       mlog_entry("(new_clusters=%d, first_new_cluster = %u)\n",
+                  new_clusters, first_new_cluster);
+
+       ret = ocfs2_journal_access(handle, bm_inode, group_bh,
+                                  OCFS2_JOURNAL_ACCESS_WRITE);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out;
+       }
+
+       group = (struct ocfs2_group_desc *)group_bh->b_data;
+
+       /* update the group first. */
+       num_bits = new_clusters * cl_bpc;
+       le16_add_cpu(&group->bg_bits, num_bits);
+       le16_add_cpu(&group->bg_free_bits_count, num_bits);
+
+       /*
+        * check whether there are some new backup superblocks exist in
+        * this group and update the group bitmap accordingly.
+        */
+       if (OCFS2_HAS_COMPAT_FEATURE(osb->sb,
+                                    OCFS2_FEATURE_COMPAT_BACKUP_SB)) {
+               backups = ocfs2_calc_new_backup_super(bm_inode,
+                                                    group,
+                                                    new_clusters,
+                                                    first_new_cluster,
+                                                    cl_cpg, 1);
+               le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
+       }
+
+       ret = ocfs2_journal_dirty(handle, group_bh);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out_rollback;
+       }
+
+       /* update the inode accordingly. */
+       ret = ocfs2_journal_access(handle, bm_inode, bm_bh,
+                                  OCFS2_JOURNAL_ACCESS_WRITE);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out_rollback;
+       }
+
+       chain = le16_to_cpu(group->bg_chain);
+       cr = (&cl->cl_recs[chain]);
+       le32_add_cpu(&cr->c_total, num_bits);
+       le32_add_cpu(&cr->c_free, num_bits);
+       le32_add_cpu(&fe->id1.bitmap1.i_total, num_bits);
+       le32_add_cpu(&fe->i_clusters, new_clusters);
+
+       if (backups) {
+               le32_add_cpu(&cr->c_free, -1 * backups);
+               le32_add_cpu(&fe->id1.bitmap1.i_used, backups);
+       }
+
+       spin_lock(&OCFS2_I(bm_inode)->ip_lock);
+       OCFS2_I(bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
+       le64_add_cpu(&fe->i_size, new_clusters << osb->s_clustersize_bits);
+       spin_unlock(&OCFS2_I(bm_inode)->ip_lock);
+       i_size_write(bm_inode, le64_to_cpu(fe->i_size));
+
+       ocfs2_journal_dirty(handle, bm_bh);
+
+out_rollback:
+       if (ret < 0) {
+               ocfs2_calc_new_backup_super(bm_inode,
+                                           group,
+                                           new_clusters,
+                                           first_new_cluster,
+                                           cl_cpg, 0);
+               le16_add_cpu(&group->bg_free_bits_count, backups);
+               le16_add_cpu(&group->bg_bits, -1 * num_bits);
+               le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);
+       }
+out:
+       mlog_exit(ret);
+       return ret;
+}
+
+static int update_backups(struct inode * inode, u32 clusters, char *data)
+{
+       int i, ret = 0;
+       u32 cluster;
+       u64 blkno;
+       struct buffer_head *backup = NULL;
+       struct ocfs2_dinode *backup_di = NULL;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+       /* calculate the real backups we need to update. */
+       for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
+               blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
+               cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
+               if (cluster > clusters)
+                       break;
+
+               ret = ocfs2_read_block(osb, blkno, &backup, 0, NULL);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       break;
+               }
+
+               memcpy(backup->b_data, data, inode->i_sb->s_blocksize);
+
+               backup_di = (struct ocfs2_dinode *)backup->b_data;
+               backup_di->i_blkno = cpu_to_le64(blkno);
+
+               ret = ocfs2_write_super_or_backup(osb, backup);
+               brelse(backup);
+               backup = NULL;
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       break;
+               }
+       }
+
+       return ret;
+}
+
+static void ocfs2_update_super_and_backups(struct inode *inode,
+                                          int new_clusters)
+{
+       int ret;
+       u32 clusters = 0;
+       struct buffer_head *super_bh = NULL;
+       struct ocfs2_dinode *super_di = NULL;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+       /*
+        * update the superblock last.
+        * It doesn't matter if the write failed.
+        */
+       ret = ocfs2_read_block(osb, OCFS2_SUPER_BLOCK_BLKNO,
+                              &super_bh, 0, NULL);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out;
+       }
+
+       super_di = (struct ocfs2_dinode *)super_bh->b_data;
+       le32_add_cpu(&super_di->i_clusters, new_clusters);
+       clusters = le32_to_cpu(super_di->i_clusters);
+
+       ret = ocfs2_write_super_or_backup(osb, super_bh);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out;
+       }
+
+       if (OCFS2_HAS_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_COMPAT_BACKUP_SB))
+               ret = update_backups(inode, clusters, super_bh->b_data);
+
+out:
+       if (super_bh)
+               brelse(super_bh);
+       if (ret)
+               printk(KERN_WARNING "ocfs2: Failed to update super blocks on %s"
+                       " during fs resize. This condition is not fatal,"
+                       " but fsck.ocfs2 should be run to fix it\n",
+                       osb->dev_str);
+       return;
+}
+
+/*
+ * Extend the filesystem to the new number of clusters specified.  This entry
+ * point is only used to extend the current filesystem to the end of the last
+ * existing group.
+ */
+int ocfs2_group_extend(struct inode * inode, int new_clusters)
+{
+       int ret;
+       handle_t *handle;
+       struct buffer_head *main_bm_bh = NULL;
+       struct buffer_head *group_bh = NULL;
+       struct inode *main_bm_inode = NULL;
+       struct ocfs2_dinode *fe = NULL;
+       struct ocfs2_group_desc *group = NULL;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       u16 cl_bpc;
+       u32 first_new_cluster;
+       u64 lgd_blkno;
+
+       mlog_entry_void();
+
+       if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+               return -EROFS;
+
+       if (new_clusters < 0)
+               return -EINVAL;
+       else if (new_clusters == 0)
+               return 0;
+
+       main_bm_inode = ocfs2_get_system_file_inode(osb,
+                                                   GLOBAL_BITMAP_SYSTEM_INODE,
+                                                   OCFS2_INVALID_SLOT);
+       if (!main_bm_inode) {
+               ret = -EINVAL;
+               mlog_errno(ret);
+               goto out;
+       }
+
+       mutex_lock(&main_bm_inode->i_mutex);
+
+       ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out_mutex;
+       }
+
+       fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
+
+       if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
+                                ocfs2_group_bitmap_size(osb->sb) * 8) {
+               mlog(ML_ERROR, "The disk is too old and small. "
+                    "Force to do offline resize.");
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+
+       if (!OCFS2_IS_VALID_DINODE(fe)) {
+               OCFS2_RO_ON_INVALID_DINODE(main_bm_inode->i_sb, fe);
+               ret = -EIO;
+               goto out_unlock;
+       }
+
+       first_new_cluster = le32_to_cpu(fe->i_clusters);
+       lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
+                                             first_new_cluster - 1);
+
+       ret = ocfs2_read_block(osb, lgd_blkno, &group_bh, OCFS2_BH_CACHED,
+                              main_bm_inode);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out_unlock;
+       }
+
+       group = (struct ocfs2_group_desc *)group_bh->b_data;
+
+       ret = ocfs2_check_group_descriptor(inode->i_sb, fe, group);
+       if (ret) {
+               mlog_errno(ret);
+               goto out_unlock;
+       }
+
+       cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
+       if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
+               le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+
+       mlog(0, "extend the last group at %llu, new clusters = %d\n",
+            le64_to_cpu(group->bg_blkno), new_clusters);
+
+       handle = ocfs2_start_trans(osb, OCFS2_GROUP_EXTEND_CREDITS);
+       if (IS_ERR(handle)) {
+               mlog_errno(PTR_ERR(handle));
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+
+       /* update the last group descriptor and inode. */
+       ret = ocfs2_update_last_group_and_inode(handle, main_bm_inode,
+                                               main_bm_bh, group_bh,
+                                               first_new_cluster,
+                                               new_clusters);
+       if (ret) {
+               mlog_errno(ret);
+               goto out_commit;
+       }
+
+       ocfs2_update_super_and_backups(main_bm_inode, new_clusters);
+
+out_commit:
+       ocfs2_commit_trans(osb, handle);
+out_unlock:
+       if (group_bh)
+               brelse(group_bh);
+
+       if (main_bm_bh)
+               brelse(main_bm_bh);
+
+       ocfs2_inode_unlock(main_bm_inode, 1);
+
+out_mutex:
+       mutex_unlock(&main_bm_inode->i_mutex);
+       iput(main_bm_inode);
+
+out:
+       mlog_exit_void();
+       return ret;
+}
diff --git a/fs/ocfs2/resize.h b/fs/ocfs2/resize.h
new file mode 100644 (file)
index 0000000..3acb79a
--- /dev/null
@@ -0,0 +1,31 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * resize.h
+ *
+ * Function prototypes
+ *
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef OCFS2_RESIZE_H
+#define OCFS2_RESIZE_H
+
+int ocfs2_group_extend(struct inode * inode, int new_clusters);
+
+#endif /* OCFS2_RESIZE_H */
index 6df4dbf67d185f6844ee96fd37bd34db387771a7..4391744e80f8aea26e36e621561d05cddb69512f 100644 (file)
@@ -101,8 +101,6 @@ static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg
 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
                                                   u64 bg_blkno,
                                                   u16 bg_bit_off);
-static inline u64 ocfs2_which_cluster_group(struct inode *inode,
-                                           u32 cluster);
 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
                                                u64 data_blkno,
                                                u64 *bg_blkno,
@@ -131,9 +129,9 @@ static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 }
 
 /* somewhat more expensive than our other checks, so use sparingly. */
-static int ocfs2_check_group_descriptor(struct super_block *sb,
-                                       struct ocfs2_dinode *di,
-                                       struct ocfs2_group_desc *gd)
+int ocfs2_check_group_descriptor(struct super_block *sb,
+                                struct ocfs2_dinode *di,
+                                struct ocfs2_group_desc *gd)
 {
        unsigned int max_bits;
 
@@ -1443,8 +1441,7 @@ static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 
 /* given a cluster offset, calculate which block group it belongs to
  * and return that block offset. */
-static inline u64 ocfs2_which_cluster_group(struct inode *inode,
-                                           u32 cluster)
+u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
 {
        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
        u32 group_no;
index cafe93703095f187a5fadf825a6415c9d1837bad..8799033bb459d9adc4b558d0e50c1b4a52562b61 100644 (file)
@@ -147,4 +147,12 @@ static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
                                      struct ocfs2_alloc_context *ac);
 
+/* given a cluster offset, calculate which block group it belongs to
+ * and return that block offset. */
+u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
+
+/* somewhat more expensive than our other checks, so use sparingly. */
+int ocfs2_check_group_descriptor(struct super_block *sb,
+                                struct ocfs2_dinode *di,
+                                struct ocfs2_group_desc *gd);
 #endif /* _CHAINALLOC_H_ */