freebsd-dev/sys/ufs/ffs/ffs_extern.h
Kirk McKusick 9b97113391 This patch corrects the first round of panics and hangs reported
with the new snapshot code.

Update addaliasu to correctly implement the semantics of the old
checkalias function. When a device vnode first comes into existence,
check to see if an anonymous vnode for the same device was created
at boot time by bdevvp(). If so, adopt the bdevvp vnode rather than
creating a new vnode for the device. This corrects a problem which
caused the kernel to panic when taking a snapshot of the root
filesystem.

Change the calling convention of vn_write_suspend_wait() to be the
same as vn_start_write().

Split out softdep_flushworklist() from softdep_flushfiles() so that
it can be used to clear the work queue when suspending filesystem
operations.

Access to buffers becomes recursive so that snapshots can recursively
traverse their indirect blocks using ffs_copyonwrite() when checking
for the need for copy on write when flushing one of their own indirect
blocks. This eliminates a deadlock between the syncer daemon and a
process taking a snapshot.

Ensure that softdep_process_worklist() can never block because of a
snapshot being taken. This eliminates a problem with buffer starvation.

Cleanup change in ffs_sync() which did not synchronously wait when
MNT_WAIT was specified. The result was an unclean filesystem panic
when doing forcible unmount with heavy filesystem I/O in progress.

Return a zero'ed block when reading a block that was not in use at
the time that a snapshot was taken. Normally, these blocks should
never be read. However, the readahead code will occationally read
them which can cause unexpected behavior.

Clean up the debugging code that ensures that no blocks be written
on a filesystem while it is suspended. Snapshots must explicitly
label the blocks that they are writing during the suspension so that
they do not cause a `write on suspended filesystem' panic.

Reorganize ffs_copyonwrite() to eliminate a deadlock and also to
prevent a race condition that would permit the same block to be
copied twice. This change eliminates an unexpected soft updates
inconsistency in fsck caused by the double allocation.

Use bqrelse rather than brelse for buffers that will be needed
soon again by the snapshot code. This improves snapshot performance.
2000-07-24 05:28:33 +00:00

141 lines
5.9 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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
/*
* Sysctl values for the fast filesystem.
*/
#define FFS_REALLOCBLKS 3 /* block reallocation enabled */
#define FFS_ASYNCFREE 4 /* asynchronous block freeing enabled */
#define FFS_MAXID 5 /* number of valid ffs ids */
#define FFS_NAMES { \
{ 0, 0 }, \
{ 0, 0 }, \
{ 0, 0 }, \
{ "doreallocblks", CTLTYPE_INT }, \
{ "doasyncfree", CTLTYPE_INT }, \
}
struct buf;
struct fid;
struct fs;
struct inode;
struct malloc_type;
struct mount;
struct proc;
struct sockaddr;
struct statfs;
struct ucred;
struct vnode;
struct vop_balloc_args;
struct vop_bmap_args;
struct vop_fsync_args;
struct vop_reallocblks_args;
struct vop_copyonwrite_args;
int ffs_alloc __P((struct inode *,
ufs_daddr_t, ufs_daddr_t, int, struct ucred *, ufs_daddr_t *));
int ffs_balloc __P((struct vop_balloc_args *));
int ffs_blkatoff __P((struct vnode *, off_t, char **, struct buf **));
void ffs_blkfree __P((struct inode *, ufs_daddr_t, long));
ufs_daddr_t ffs_blkpref __P((struct inode *, ufs_daddr_t, int, ufs_daddr_t *));
int ffs_bmap __P((struct vop_bmap_args *));
void ffs_clrblock __P((struct fs *, u_char *, ufs_daddr_t));
int ffs_copyonwrite __P((struct vop_copyonwrite_args *ap));
int ffs_fhtovp __P((struct mount *, struct fid *, struct vnode **));
int ffs_flushfiles __P((struct mount *, int, struct proc *));
void ffs_fragacct __P((struct fs *, int, int32_t [], int));
int ffs_freefile __P(( struct vnode *, ino_t, int ));
int ffs_isblock __P((struct fs *, u_char *, ufs_daddr_t));
int ffs_isfreeblock __P((struct fs *, unsigned char *, ufs_daddr_t));
int ffs_mountfs __P((struct vnode *, struct mount *, struct proc *,
struct malloc_type *));
int ffs_mountroot __P((void));
int ffs_reallocblks __P((struct vop_reallocblks_args *));
int ffs_realloccg __P((struct inode *,
ufs_daddr_t, ufs_daddr_t, int, int, struct ucred *, struct buf **));
void ffs_setblock __P((struct fs *, u_char *, ufs_daddr_t));
int ffs_snapblkfree __P((struct inode *freeip, ufs_daddr_t bno, long size));
int ffs_snapshot __P((struct mount *mp, char *snapfile));
void ffs_snapshot_mount __P((struct mount *mp));
void ffs_snapshot_unmount __P((struct mount *mp));
int ffs_statfs __P((struct mount *, struct statfs *, struct proc *));
int ffs_sync __P((struct mount *, int, struct ucred *, struct proc *));
int ffs_truncate __P((struct vnode *, off_t, int, struct ucred *, struct proc *));
int ffs_unmount __P((struct mount *, int, struct proc *));
int ffs_update __P((struct vnode *, int));
int ffs_valloc __P((struct vnode *, int, struct ucred *, struct vnode **));
int ffs_vfree __P((struct vnode *, ino_t, int));
int ffs_vget __P((struct mount *, ino_t, struct vnode **));
int ffs_vptofh __P((struct vnode *, struct fid *));
extern vop_t **ffs_vnodeop_p;
extern vop_t **ffs_specop_p;
extern vop_t **ffs_fifoop_p;
/*
* Soft update function prototypes.
*/
void softdep_initialize __P((void));
int softdep_mount __P((struct vnode *, struct mount *, struct fs *,
struct ucred *));
int softdep_flushworklist __P((struct mount *, int *, struct proc *));
int softdep_flushfiles __P((struct mount *, int, struct proc *));
void softdep_update_inodeblock __P((struct inode *, struct buf *, int));
void softdep_load_inodeblock __P((struct inode *));
void softdep_freefile __P((struct vnode *, ino_t, int));
void softdep_setup_freeblocks __P((struct inode *, off_t));
void softdep_setup_inomapdep __P((struct buf *, struct inode *, ino_t));
void softdep_setup_blkmapdep __P((struct buf *, struct fs *, ufs_daddr_t));
void softdep_setup_allocdirect __P((struct inode *, ufs_lbn_t, ufs_daddr_t,
ufs_daddr_t, long, long, struct buf *));
void softdep_setup_allocindir_meta __P((struct buf *, struct inode *,
struct buf *, int, ufs_daddr_t));
void softdep_setup_allocindir_page __P((struct inode *, ufs_lbn_t,
struct buf *, int, ufs_daddr_t, ufs_daddr_t, struct buf *));
void softdep_fsync_mountdev __P((struct vnode *));
int softdep_sync_metadata __P((struct vop_fsync_args *));
/* XXX incorrectly moved to mount.h - should be indirect function */
#if 0
int softdep_fsync __P((struct vnode *vp));
#endif
#endif /* !_UFS_FFS_EXTERN_H */