kernel-fxtec-pro1x/fs/ocfs2/dlmglue.h
Jan Kara 84d86f83f9 ocfs2: avoid blocking in ocfs2_mark_lockres_freeing() in downconvert thread
If we are dropping last inode reference from downconvert thread, we will
end up calling ocfs2_mark_lockres_freeing() which can block if the lock
we are freeing is queued thus creating an A-A deadlock.  Luckily, since
we are the downconvert thread, we can immediately dequeue the lock and
thus avoid waiting in this case.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:55 -07:00

173 lines
5.8 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* dlmglue.h
*
* description here
*
* Copyright (C) 2002, 2004 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 DLMGLUE_H
#define DLMGLUE_H
#include "dcache.h"
#define OCFS2_LVB_VERSION 5
struct ocfs2_meta_lvb {
__u8 lvb_version;
__u8 lvb_reserved0;
__be16 lvb_idynfeatures;
__be32 lvb_iclusters;
__be32 lvb_iuid;
__be32 lvb_igid;
__be64 lvb_iatime_packed;
__be64 lvb_ictime_packed;
__be64 lvb_imtime_packed;
__be64 lvb_isize;
__be16 lvb_imode;
__be16 lvb_inlink;
__be32 lvb_iattr;
__be32 lvb_igeneration;
__be32 lvb_reserved2;
};
#define OCFS2_QINFO_LVB_VERSION 1
struct ocfs2_qinfo_lvb {
__u8 lvb_version;
__u8 lvb_reserved[3];
__be32 lvb_bgrace;
__be32 lvb_igrace;
__be32 lvb_syncms;
__be32 lvb_blocks;
__be32 lvb_free_blk;
__be32 lvb_free_entry;
};
#define OCFS2_ORPHAN_LVB_VERSION 1
struct ocfs2_orphan_scan_lvb {
__u8 lvb_version;
__u8 lvb_reserved[3];
__be32 lvb_os_seqno;
};
/* ocfs2_inode_lock_full() 'arg_flags' flags */
/* don't wait on recovery. */
#define OCFS2_META_LOCK_RECOVERY (0x01)
/* Instruct the dlm not to queue ourselves on the other node. */
#define OCFS2_META_LOCK_NOQUEUE (0x02)
/* don't block waiting for the downconvert thread, instead return -EAGAIN */
#define OCFS2_LOCK_NONBLOCK (0x04)
/* Locking subclasses of inode cluster lock */
enum {
OI_LS_NORMAL = 0,
OI_LS_PARENT,
OI_LS_RENAME1,
OI_LS_RENAME2,
OI_LS_REFLINK_TARGET,
};
int ocfs2_dlm_init(struct ocfs2_super *osb);
void ocfs2_dlm_shutdown(struct ocfs2_super *osb, int hangup_pending);
void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res);
void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
enum ocfs2_lock_type type,
unsigned int generation,
struct inode *inode);
void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
u64 parent, struct inode *inode);
struct ocfs2_file_private;
void ocfs2_file_lock_res_init(struct ocfs2_lock_res *lockres,
struct ocfs2_file_private *fp);
struct ocfs2_mem_dqinfo;
void ocfs2_qinfo_lock_res_init(struct ocfs2_lock_res *lockres,
struct ocfs2_mem_dqinfo *info);
void ocfs2_refcount_lock_res_init(struct ocfs2_lock_res *lockres,
struct ocfs2_super *osb, u64 ref_blkno,
unsigned int generation);
void ocfs2_lock_res_free(struct ocfs2_lock_res *res);
int ocfs2_create_new_inode_locks(struct inode *inode);
int ocfs2_drop_inode_locks(struct inode *inode);
int ocfs2_rw_lock(struct inode *inode, int write);
void ocfs2_rw_unlock(struct inode *inode, int write);
int ocfs2_open_lock(struct inode *inode);
int ocfs2_try_open_lock(struct inode *inode, int write);
void ocfs2_open_unlock(struct inode *inode);
int ocfs2_inode_lock_atime(struct inode *inode,
struct vfsmount *vfsmnt,
int *level);
int ocfs2_inode_lock_full_nested(struct inode *inode,
struct buffer_head **ret_bh,
int ex,
int arg_flags,
int subclass);
int ocfs2_inode_lock_with_page(struct inode *inode,
struct buffer_head **ret_bh,
int ex,
struct page *page);
/* Variants without special locking class or flags */
#define ocfs2_inode_lock_full(i, r, e, f)\
ocfs2_inode_lock_full_nested(i, r, e, f, OI_LS_NORMAL)
#define ocfs2_inode_lock_nested(i, b, e, s)\
ocfs2_inode_lock_full_nested(i, b, e, 0, s)
/* 99% of the time we don't want to supply any additional flags --
* those are for very specific cases only. */
#define ocfs2_inode_lock(i, b, e) ocfs2_inode_lock_full_nested(i, b, e, 0, OI_LS_NORMAL)
void ocfs2_inode_unlock(struct inode *inode,
int ex);
int ocfs2_super_lock(struct ocfs2_super *osb,
int ex);
void ocfs2_super_unlock(struct ocfs2_super *osb,
int ex);
int ocfs2_orphan_scan_lock(struct ocfs2_super *osb, u32 *seqno);
void ocfs2_orphan_scan_unlock(struct ocfs2_super *osb, u32 seqno);
int ocfs2_rename_lock(struct ocfs2_super *osb);
void ocfs2_rename_unlock(struct ocfs2_super *osb);
int ocfs2_nfs_sync_lock(struct ocfs2_super *osb, int ex);
void ocfs2_nfs_sync_unlock(struct ocfs2_super *osb, int ex);
int ocfs2_dentry_lock(struct dentry *dentry, int ex);
void ocfs2_dentry_unlock(struct dentry *dentry, int ex);
int ocfs2_file_lock(struct file *file, int ex, int trylock);
void ocfs2_file_unlock(struct file *file);
int ocfs2_qinfo_lock(struct ocfs2_mem_dqinfo *oinfo, int ex);
void ocfs2_qinfo_unlock(struct ocfs2_mem_dqinfo *oinfo, int ex);
struct ocfs2_refcount_tree;
int ocfs2_refcount_lock(struct ocfs2_refcount_tree *ref_tree, int ex);
void ocfs2_refcount_unlock(struct ocfs2_refcount_tree *ref_tree, int ex);
void ocfs2_mark_lockres_freeing(struct ocfs2_super *osb,
struct ocfs2_lock_res *lockres);
void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
struct ocfs2_lock_res *lockres);
/* for the downconvert thread */
void ocfs2_wake_downconvert_thread(struct ocfs2_super *osb);
struct ocfs2_dlm_debug *ocfs2_new_dlm_debug(void);
void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug);
/* To set the locking protocol on module initialization */
void ocfs2_set_locking_protocol(void);
#endif /* DLMGLUE_H */