freebsd-skq/sys/ufs/ffs/ffs_extern.h
kib fdd50404d1 Cylinder group bitmaps and blocks containing inode for a snapshot
file are after snaplock, while other ffs device buffers are before
snaplock in global lock order. By itself, this could cause deadlock
when bdwrite() tries to flush dirty buffers on snapshotted ffs. If,
during the flush, COW activity for snapshot needs to allocate block
and ffs_alloccg() selects the cylinder group that is being written
by bdwrite(), then kernel would panic due to recursive buffer lock
acquision.

Avoid dealing with buffers in bdwrite() that are from other side of
snaplock divisor in the lock order then the buffer being written. Add
new BOP, bop_bdwrite(), to do dirty buffer flushing for same vnode in
the bdwrite(). Default implementation, bufbdflush(), refactors the code
from bdwrite(). For ffs device buffers, specialized implementation is
used.

Reviewed by:	tegge, jeff, Russell Cattelan (cattelan xfs org, xfs changes)
Tested by:	Peter Holm
X-MFC after:	3 weeks (if ever: it changes ABI)
2007-01-23 10:01:19 +00:00

132 lines
5.7 KiB
C

/*-
* Copyright (c) 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ffs_extern.h 8.6 (Berkeley) 3/30/95
* $FreeBSD$
*/
#ifndef _UFS_FFS_EXTERN_H
#define _UFS_FFS_EXTERN_H
struct buf;
struct cg;
struct fid;
struct fs;
struct inode;
struct malloc_type;
struct mount;
struct thread;
struct sockaddr;
struct statfs;
struct ucred;
struct vnode;
struct vop_fsync_args;
struct vop_reallocblks_args;
int ffs_alloc(struct inode *,
ufs2_daddr_t, ufs2_daddr_t, int, struct ucred *, ufs2_daddr_t *);
int ffs_balloc_ufs1(struct vnode *a_vp, off_t a_startoffset, int a_size,
struct ucred *a_cred, int a_flags, struct buf **a_bpp);
int ffs_balloc_ufs2(struct vnode *a_vp, off_t a_startoffset, int a_size,
struct ucred *a_cred, int a_flags, struct buf **a_bpp);
int ffs_blkatoff(struct vnode *, off_t, char **, struct buf **);
void ffs_blkfree(struct ufsmount *, struct fs *, struct vnode *,
ufs2_daddr_t, long, ino_t);
ufs2_daddr_t ffs_blkpref_ufs1(struct inode *, ufs_lbn_t, int, ufs1_daddr_t *);
ufs2_daddr_t ffs_blkpref_ufs2(struct inode *, ufs_lbn_t, int, ufs2_daddr_t *);
int ffs_checkfreefile(struct fs *, struct vnode *, ino_t);
void ffs_clrblock(struct fs *, u_char *, ufs1_daddr_t);
void ffs_bdflush(struct bufobj *, struct buf *);
int ffs_copyonwrite(struct vnode *, struct buf *);
int ffs_flushfiles(struct mount *, int, struct thread *);
void ffs_fragacct(struct fs *, int, int32_t [], int);
int ffs_freefile(struct ufsmount *, struct fs *, struct vnode *, ino_t,
int);
int ffs_isblock(struct fs *, u_char *, ufs1_daddr_t);
void ffs_load_inode(struct buf *, struct inode *, struct fs *, ino_t);
int ffs_mountroot(void);
int ffs_reallocblks(struct vop_reallocblks_args *);
int ffs_realloccg(struct inode *, ufs2_daddr_t, ufs2_daddr_t,
ufs2_daddr_t, int, int, struct ucred *, struct buf **);
int ffs_sbupdate(struct ufsmount *, int, int);
void ffs_setblock(struct fs *, u_char *, ufs1_daddr_t);
int ffs_snapblkfree(struct fs *, struct vnode *, ufs2_daddr_t, long, ino_t);
void ffs_snapremove(struct vnode *vp);
int ffs_snapshot(struct mount *mp, char *snapfile);
void ffs_snapshot_mount(struct mount *mp);
void ffs_snapshot_unmount(struct mount *mp);
int ffs_syncvnode(struct vnode *vp, int waitfor);
int ffs_truncate(struct vnode *, off_t, int, struct ucred *, struct thread *);
int ffs_update(struct vnode *, int);
int ffs_valloc(struct vnode *, int, struct ucred *, struct vnode **);
int ffs_vfree(struct vnode *, ino_t, int);
vfs_vget_t ffs_vget;
extern struct vop_vector ffs_vnodeops1;
extern struct vop_vector ffs_fifoops1;
extern struct vop_vector ffs_vnodeops2;
extern struct vop_vector ffs_fifoops2;
/*
* Soft update function prototypes.
*/
int softdep_check_suspend(struct mount *, struct vnode *,
int, int, int, int);
void softdep_get_depcounts(struct mount *, int *, int *);
void softdep_initialize(void);
void softdep_uninitialize(void);
int softdep_mount(struct vnode *, struct mount *, struct fs *,
struct ucred *);
void softdep_move_dependencies(struct buf *, struct buf *);
int softdep_flushworklist(struct mount *, int *, struct thread *);
int softdep_flushfiles(struct mount *, int, struct thread *);
void softdep_update_inodeblock(struct inode *, struct buf *, int);
void softdep_load_inodeblock(struct inode *);
void softdep_freefile(struct vnode *, ino_t, int);
int softdep_request_cleanup(struct fs *, struct vnode *);
void softdep_setup_freeblocks(struct inode *, off_t, int);
void softdep_setup_inomapdep(struct buf *, struct inode *, ino_t);
void softdep_setup_blkmapdep(struct buf *, struct mount *, ufs2_daddr_t);
void softdep_setup_allocdirect(struct inode *, ufs_lbn_t, ufs2_daddr_t,
ufs2_daddr_t, long, long, struct buf *);
void softdep_setup_allocext(struct inode *, ufs_lbn_t, ufs2_daddr_t,
ufs2_daddr_t, long, long, struct buf *);
void softdep_setup_allocindir_meta(struct buf *, struct inode *,
struct buf *, int, ufs2_daddr_t);
void softdep_setup_allocindir_page(struct inode *, ufs_lbn_t,
struct buf *, int, ufs2_daddr_t, ufs2_daddr_t, struct buf *);
void softdep_fsync_mountdev(struct vnode *);
int softdep_sync_metadata(struct vnode *);
int softdep_process_worklist(struct mount *, int);
int softdep_fsync(struct vnode *);
int softdep_waitidle(struct mount *);
#endif /* !_UFS_FFS_EXTERN_H */