+/*
+ * ocfs2_open_lock always get PR mode lock.
+ */
+int ocfs2_open_lock(struct inode *inode)
+{
+ int status = 0;
+ struct ocfs2_lock_res *lockres;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ BUG_ON(!inode);
+
+ mlog_entry_void();
+
+ mlog(0, "inode %llu take PRMODE open lock\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
+
+ if (ocfs2_mount_local(osb))
+ goto out;
+
+ lockres = &OCFS2_I(inode)->ip_open_lockres;
+
+ status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
+ LKM_PRMODE, 0, 0);
+ if (status < 0)
+ mlog_errno(status);
+
+out:
+ mlog_exit(status);
+ return status;
+}
+
+int ocfs2_try_open_lock(struct inode *inode, int write)
+{
+ int status = 0, level;
+ struct ocfs2_lock_res *lockres;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ BUG_ON(!inode);
+
+ mlog_entry_void();
+
+ mlog(0, "inode %llu try to take %s open lock\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ write ? "EXMODE" : "PRMODE");
+
+ if (ocfs2_mount_local(osb))
+ goto out;
+
+ lockres = &OCFS2_I(inode)->ip_open_lockres;
+
+ level = write ? LKM_EXMODE : LKM_PRMODE;
+
+ /*
+ * The file system may already holding a PRMODE/EXMODE open lock.
+ * Since we pass LKM_NOQUEUE, the request won't block waiting on
+ * other nodes and the -EAGAIN will indicate to the caller that
+ * this inode is still in use.
+ */
+ status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
+ level, LKM_NOQUEUE, 0);
+
+out:
+ mlog_exit(status);
+ return status;
+}
+
+/*
+ * ocfs2_open_unlock unlock PR and EX mode open locks.
+ */
+void ocfs2_open_unlock(struct inode *inode)
+{
+ struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_open_lockres;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ mlog_entry_void();
+
+ mlog(0, "inode %llu drop open lock\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
+
+ if (ocfs2_mount_local(osb))
+ goto out;
+
+ if(lockres->l_ro_holders)
+ ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
+ LKM_PRMODE);
+ if(lockres->l_ex_holders)
+ ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
+ LKM_EXMODE);
+
+out:
+ mlog_exit_void();
+}
+