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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/ocfs2/resize.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/fs/ocfs2/resize.c')
-rw-r--r--kernel/fs/ocfs2/resize.c589
1 files changed, 589 insertions, 0 deletions
diff --git a/kernel/fs/ocfs2/resize.c b/kernel/fs/ocfs2/resize.c
new file mode 100644
index 000000000..d5da6f624
--- /dev/null
+++ b/kernel/fs/ocfs2/resize.c
@@ -0,0 +1,589 @@
+/* -*- 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>
+
+#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 "ocfs2_trace.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,
+ 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++;
+ }
+
+ 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);
+
+ trace_ocfs2_update_last_group_and_inode(new_clusters,
+ first_new_cluster);
+
+ ret = ocfs2_journal_access_gd(handle, INODE_CACHE(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,
+ cl_cpg, 1);
+ le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
+ }
+
+ ocfs2_journal_dirty(handle, group_bh);
+
+ /* update the inode accordingly. */
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(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, (u64)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,
+ 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:
+ if (ret)
+ mlog_errno(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_blocks_sync(osb, blkno, 1, &backup);
+ 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_blocks_sync(osb, OCFS2_SUPER_BLOCK_BLKNO, 1,
+ &super_bh);
+ 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:
+ 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;
+
+ 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;
+
+ /* main_bm_bh is validated by inode read inside ocfs2_inode_lock(),
+ * so any corruption is a code bug. */
+ BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
+
+ if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
+ ocfs2_group_bitmap_size(osb->sb, 0,
+ osb->s_feature_incompat) * 8) {
+ mlog(ML_ERROR, "The disk is too old and small. "
+ "Force to do offline resize.");
+ ret = -EINVAL;
+ 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_group_descriptor(main_bm_inode, fe, lgd_blkno,
+ &group_bh);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+ group = (struct ocfs2_group_desc *)group_bh->b_data;
+
+ 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;
+ }
+
+
+ trace_ocfs2_group_extend(
+ (unsigned long long)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:
+ brelse(group_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:
+ return ret;
+}
+
+static int ocfs2_check_new_group(struct inode *inode,
+ struct ocfs2_dinode *di,
+ struct ocfs2_new_group_input *input,
+ struct buffer_head *group_bh)
+{
+ int ret;
+ struct ocfs2_group_desc *gd =
+ (struct ocfs2_group_desc *)group_bh->b_data;
+ u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);
+
+ ret = ocfs2_check_group_descriptor(inode->i_sb, di, group_bh);
+ if (ret)
+ goto out;
+
+ ret = -EINVAL;
+ if (le16_to_cpu(gd->bg_chain) != input->chain)
+ mlog(ML_ERROR, "Group descriptor # %llu has bad chain %u "
+ "while input has %u set.\n",
+ (unsigned long long)le64_to_cpu(gd->bg_blkno),
+ le16_to_cpu(gd->bg_chain), input->chain);
+ else if (le16_to_cpu(gd->bg_bits) != input->clusters * cl_bpc)
+ mlog(ML_ERROR, "Group descriptor # %llu has bit count %u but "
+ "input has %u clusters set\n",
+ (unsigned long long)le64_to_cpu(gd->bg_blkno),
+ le16_to_cpu(gd->bg_bits), input->clusters);
+ else if (le16_to_cpu(gd->bg_free_bits_count) != input->frees * cl_bpc)
+ mlog(ML_ERROR, "Group descriptor # %llu has free bit count %u "
+ "but it should have %u set\n",
+ (unsigned long long)le64_to_cpu(gd->bg_blkno),
+ le16_to_cpu(gd->bg_bits),
+ input->frees * cl_bpc);
+ else
+ ret = 0;
+
+out:
+ return ret;
+}
+
+static int ocfs2_verify_group_and_input(struct inode *inode,
+ struct ocfs2_dinode *di,
+ struct ocfs2_new_group_input *input,
+ struct buffer_head *group_bh)
+{
+ u16 cl_count = le16_to_cpu(di->id2.i_chain.cl_count);
+ u16 cl_cpg = le16_to_cpu(di->id2.i_chain.cl_cpg);
+ u16 next_free = le16_to_cpu(di->id2.i_chain.cl_next_free_rec);
+ u32 cluster = ocfs2_blocks_to_clusters(inode->i_sb, input->group);
+ u32 total_clusters = le32_to_cpu(di->i_clusters);
+ int ret = -EINVAL;
+
+ if (cluster < total_clusters)
+ mlog(ML_ERROR, "add a group which is in the current volume.\n");
+ else if (input->chain >= cl_count)
+ mlog(ML_ERROR, "input chain exceeds the limit.\n");
+ else if (next_free != cl_count && next_free != input->chain)
+ mlog(ML_ERROR,
+ "the add group should be in chain %u\n", next_free);
+ else if (total_clusters + input->clusters < total_clusters)
+ mlog(ML_ERROR, "add group's clusters overflow.\n");
+ else if (input->clusters > cl_cpg)
+ mlog(ML_ERROR, "the cluster exceeds the maximum of a group\n");
+ else if (input->frees > input->clusters)
+ mlog(ML_ERROR, "the free cluster exceeds the total clusters\n");
+ else if (total_clusters % cl_cpg != 0)
+ mlog(ML_ERROR,
+ "the last group isn't full. Use group extend first.\n");
+ else if (input->group != ocfs2_which_cluster_group(inode, cluster))
+ mlog(ML_ERROR, "group blkno is invalid\n");
+ else if ((ret = ocfs2_check_new_group(inode, di, input, group_bh)))
+ mlog(ML_ERROR, "group descriptor check failed.\n");
+ else
+ ret = 0;
+
+ return ret;
+}
+
+/* Add a new group descriptor to global_bitmap. */
+int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input)
+{
+ int ret;
+ handle_t *handle;
+ struct buffer_head *main_bm_bh = NULL;
+ struct inode *main_bm_inode = NULL;
+ struct ocfs2_dinode *fe = NULL;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct buffer_head *group_bh = NULL;
+ struct ocfs2_group_desc *group = NULL;
+ struct ocfs2_chain_list *cl;
+ struct ocfs2_chain_rec *cr;
+ u16 cl_bpc;
+ u64 bg_ptr;
+
+ if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+ return -EROFS;
+
+ 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, 0,
+ osb->s_feature_incompat) * 8) {
+ mlog(ML_ERROR, "The disk is too old and small."
+ " Force to do offline resize.");
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ ret = ocfs2_read_blocks_sync(osb, input->group, 1, &group_bh);
+ if (ret < 0) {
+ mlog(ML_ERROR, "Can't read the group descriptor # %llu "
+ "from the device.", (unsigned long long)input->group);
+ goto out_unlock;
+ }
+
+ ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), group_bh);
+
+ ret = ocfs2_verify_group_and_input(main_bm_inode, fe, input, group_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_free_group_bh;
+ }
+
+ trace_ocfs2_group_add((unsigned long long)input->group,
+ input->chain, input->clusters, input->frees);
+
+ handle = ocfs2_start_trans(osb, OCFS2_GROUP_ADD_CREDITS);
+ if (IS_ERR(handle)) {
+ mlog_errno(PTR_ERR(handle));
+ ret = -EINVAL;
+ goto out_free_group_bh;
+ }
+
+ cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
+ cl = &fe->id2.i_chain;
+ cr = &cl->cl_recs[input->chain];
+
+ ret = ocfs2_journal_access_gd(handle, INODE_CACHE(main_bm_inode),
+ group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ group = (struct ocfs2_group_desc *)group_bh->b_data;
+ bg_ptr = le64_to_cpu(group->bg_next_group);
+ group->bg_next_group = cr->c_blkno;
+ ocfs2_journal_dirty(handle, group_bh);
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(main_bm_inode),
+ main_bm_bh, OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret < 0) {
+ group->bg_next_group = cpu_to_le64(bg_ptr);
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ if (input->chain == le16_to_cpu(cl->cl_next_free_rec)) {
+ le16_add_cpu(&cl->cl_next_free_rec, 1);
+ memset(cr, 0, sizeof(struct ocfs2_chain_rec));
+ }
+
+ cr->c_blkno = cpu_to_le64(input->group);
+ le32_add_cpu(&cr->c_total, input->clusters * cl_bpc);
+ le32_add_cpu(&cr->c_free, input->frees * cl_bpc);
+
+ le32_add_cpu(&fe->id1.bitmap1.i_total, input->clusters *cl_bpc);
+ le32_add_cpu(&fe->id1.bitmap1.i_used,
+ (input->clusters - input->frees) * cl_bpc);
+ le32_add_cpu(&fe->i_clusters, input->clusters);
+
+ ocfs2_journal_dirty(handle, main_bm_bh);
+
+ spin_lock(&OCFS2_I(main_bm_inode)->ip_lock);
+ OCFS2_I(main_bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
+ le64_add_cpu(&fe->i_size, (u64)input->clusters << osb->s_clustersize_bits);
+ spin_unlock(&OCFS2_I(main_bm_inode)->ip_lock);
+ i_size_write(main_bm_inode, le64_to_cpu(fe->i_size));
+
+ ocfs2_update_super_and_backups(main_bm_inode, input->clusters);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+
+out_free_group_bh:
+ brelse(group_bh);
+
+out_unlock:
+ 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:
+ return ret;
+}