freebsd-skq/sys/miscfs/devfs/devfs_vfsops.c
1999-01-27 22:42:27 +00:00

354 lines
9.2 KiB
C

/*-
* Copyright 1997,1998 Julian Elischer. All rights reserved.
* julian@freebsd.org
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER ``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 HOLDER 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.
*
* $Id: devfs_vfsops.c,v 1.35 1998/12/07 21:58:30 archie Exp $
*
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/malloc.h>
#include <miscfs/devfs/devfsdefs.h>
static MALLOC_DEFINE(M_DEVFSMNT, "DEVFS mount", "DEVFS mount structure");
static int devfs_statfs( struct mount *mp, struct statfs *sbp, struct proc *p);
/*-
* Called from the generic VFS startups.
* This is the second stage of DEVFS initialisation.
* The probed devices have already been loaded and the
* basic structure of the DEVFS created.
* We take the oportunity to mount the hidden DEVFS layer, so that
* devices from devfs get sync'd.
*/
static int
devfs_init(struct vfsconf *vfsp)
{
struct mount *mp = dev_root->dnp->dvm->mount;
/*-
* fill in the missing members on the "hidden" mount
* we could almost use vfs_rootmountalloc() to do this.
*/
lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0);
mp->mnt_op = vfsp->vfc_vfsops;
mp->mnt_vfc = vfsp;
mp->mnt_stat.f_type = vfsp->vfc_typenum;
mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK;
strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN);
mp->mnt_vnodecovered = NULLVP;
/* Mark a reference for the "invisible" blueprint mount */
mp->mnt_vfc->vfc_refcount++;
CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
printf("DEVFS: ready to run\n");
return 0; /*XXX*/
}
/*-
* mp - pointer to 'mount' structure
* path - addr in user space of mount point (ie /usr or whatever)
* data - addr in user space of mount params including the
* name of the block special file to treat as a filesystem.
* ndp - namei data pointer
* p - proc pointer
* devfs is special in that it doesn't require any device to be mounted..
* It makes up its data as it goes along.
* it must be mounted during single user.. until it is, only std{in/out/err}
* and the root filesystem are available.
*/
/*proto*/
int
devfs_mount(struct mount *mp, char *path, caddr_t data,
struct nameidata *ndp, struct proc *p)
{
struct devfsmount *devfs_mp_p; /* devfs specific mount info */
int error;
u_int size;
DBPRINT(("mount "));
/*-
* If they just want to update, we don't need to do anything.
*/
if (mp->mnt_flag & MNT_UPDATE)
{
return 0;
}
/*-
* Well, it's not an update, it's a real mount request.
* Time to get dirty.
* HERE we should check to see if we are already mounted here.
*/
devfs_mp_p = (struct devfsmount *)malloc(sizeof *devfs_mp_p,
M_DEVFSMNT, M_WAITOK);
if (devfs_mp_p == NULL)
return (ENOMEM);
bzero(devfs_mp_p,sizeof(*devfs_mp_p));
devfs_mp_p->mount = mp;
/*-
* Fill out some fields
*/
mp->mnt_data = (qaddr_t)devfs_mp_p;
if (mp->mnt_vfc == NULL)
mp->mnt_stat.f_type = -1; /* doing hidden mountpoint */
else
mp->mnt_stat.f_type = mp->mnt_vfc->vfc_typenum;
mp->mnt_stat.f_fsid.val[0] = (intptr_t)(void *)devfs_mp_p;
mp->mnt_stat.f_fsid.val[1] = mp->mnt_stat.f_type;
mp->mnt_flag |= MNT_LOCAL;
if((error = dev_dup_plane(devfs_mp_p)) != 0)
{
mp->mnt_data = (qaddr_t)0;
free((caddr_t)devfs_mp_p, M_DEVFSMNT);
return (error);
}
/*-
* Copy in the name of the directory the filesystem
* is to be mounted on.
* And we clear the remainder of the character strings
* to be tidy.
* Then, we try to fill in the filesystem stats structure
* as best we can with whatever we can think of at the time
*/
if(devfs_up_and_going) {
copyinstr(path, (caddr_t)mp->mnt_stat.f_mntonname,
sizeof(mp->mnt_stat.f_mntonname)-1, &size);
bzero(mp->mnt_stat.f_mntonname + size,
sizeof(mp->mnt_stat.f_mntonname) - size);
} else {
bcopy("dummy_mount", (caddr_t)mp->mnt_stat.f_mntonname,12);
}
bzero(mp->mnt_stat.f_mntfromname , MNAMELEN );
bcopy("devfs",mp->mnt_stat.f_mntfromname, 5);
(void)devfs_statfs(mp, &mp->mnt_stat, p);
return 0;
}
static int
devfs_start(struct mount *mp, int flags, struct proc *p)
{
DBPRINT(("start "));
return 0;
}
/*-
* Unmount the filesystem described by mp.
*/
static int
devfs_unmount( struct mount *mp, int mntflags, struct proc *p)
{
struct devfsmount *devfs_mp_p = (struct devfsmount *)mp->mnt_data;
int flags = 0;
int error;
if (mntflags & MNT_FORCE) {
flags |= FORCECLOSE;
}
error = vflush(mp, NULLVP, flags);
if (error)
return error;
DBPRINT(("unmount "));
devfs_free_plane(devfs_mp_p);
free((caddr_t)devfs_mp_p, M_DEVFSMNT);
mp->mnt_data = (qaddr_t)0;
mp->mnt_flag &= ~MNT_LOCAL;
return 0;
}
/* return the address of the root vnode in *vpp */
static int
devfs_root(struct mount *mp, struct vnode **vpp)
{
struct devfsmount *devfs_mp_p = (struct devfsmount *)(mp->mnt_data);
DBPRINT(("root "));
devfs_dntovn(devfs_mp_p->plane_root->dnp,vpp);
return 0;
}
static int
devfs_quotactl(struct mount *mp, int cmds, uid_t uid, caddr_t arg,
struct proc *p)
{
DBPRINT(("quotactl "));
return EOPNOTSUPP;
}
static int
devfs_statfs( struct mount *mp, struct statfs *sbp, struct proc *p)
{
struct devfsmount *devfs_mp_p = (struct devfsmount *)mp->mnt_data;
/*-
* Fill in the stat block.
*/
DBPRINT(("statfs "));
sbp->f_type = mp->mnt_stat.f_type;
sbp->f_flags = 0; /* XXX */
sbp->f_bsize = 128;
sbp->f_iosize = 1024; /* XXX*/
sbp->f_blocks = 128;
sbp->f_bfree = 0;
sbp->f_bavail = 0;
sbp->f_files = 128;
sbp->f_ffree = 0; /* what to put in here? */
sbp->f_fsid.val[0] = (intptr_t)(void *)devfs_mp_p;
sbp->f_fsid.val[1] = mp->mnt_stat.f_type;
/*-
* Copy the mounted on and mounted from names into
* the passed in stat block, if it is not the one
* in the mount structure.
*/
if (sbp != &mp->mnt_stat) {
bcopy((caddr_t)mp->mnt_stat.f_mntonname,
(caddr_t)&sbp->f_mntonname[0], MNAMELEN);
bcopy((caddr_t)mp->mnt_stat.f_mntfromname,
(caddr_t)&sbp->f_mntfromname[0], MNAMELEN);
}
return 0;
}
/*-
* Go through the disk queues to initiate sandbagged IO;
* go through the inodes to write those that have been modified;
* initiate the writing of the super block if it has been modified.
*
* Note: we are always called with the filesystem marked `MPBUSY'.
*/
static int
devfs_sync(struct mount *mp, int waitfor,struct ucred *cred,struct proc *p)
{
register struct vnode *vp, *nvp;
int error, allerror = 0;
DBPRINT(("sync "));
/*-
* Write back modified superblock.
* Consistency check that the superblock
* is still in the buffer cache.
*/
/*-
* Write back each (modified) inode.
*/
loop:
for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nvp) {
/*-
* If the vnode that we are about to sync is no longer
* associated with this mount point, start over.
*/
if (vp->v_mount != mp)
goto loop;
nvp = vp->v_mntvnodes.le_next;
if (VOP_ISLOCKED(vp))
continue;
if (TAILQ_EMPTY(&vp->v_dirtyblkhd))
continue;
if (vp->v_type == VBLK) {
if (vget(vp, LK_EXCLUSIVE, p))
goto loop;
error = VOP_FSYNC(vp, cred, waitfor, p);
if (error)
allerror = error;
vput(vp);
}
#ifdef NOTYET
else {
struct timeval tv;
tv = time;
/* VOP_UPDATE(vp, &tv, &tv, waitfor == MNT_WAIT); */
VOP_UPDATE(vp, &tv, &tv, 0);
}
#endif
}
/*-
* Force stale file system control information to be flushed.
*( except that htat makes no sense with devfs
*/
return (allerror);
}
static int
devfs_vget(struct mount *mp, ino_t ino,struct vnode **vpp)
{
DBPRINT(("vget "));
return EOPNOTSUPP;
}
/*************************************************************
* The concept of exporting a kernel generated devfs is stupid
* So don't handle filehandles
*/
static int
devfs_fhtovp (struct mount *mp, struct fid *fhp, struct sockaddr *nam,
struct vnode **vpp, int *exflagsp, struct ucred **credanonp)
{
DBPRINT(("fhtovp "));
return (EINVAL);
}
static int
devfs_vptofh (struct vnode *vp, struct fid *fhp)
{
DBPRINT(("vptofh "));
return (EINVAL);
}
static struct vfsops devfs_vfsops = {
devfs_mount,
devfs_start,
devfs_unmount,
devfs_root,
devfs_quotactl,
devfs_statfs,
devfs_sync,
devfs_vget,
devfs_fhtovp,
devfs_vptofh,
devfs_init
};
VFS_SET(devfs_vfsops, devfs, 0);