386BSD 0.1 development

[unix-history] / usr / src / sys.386bsd / isofs / isofs_vfsops.c

#include "param.h"
#include "systm.h"
#include "namei.h"
#include "proc.h"
#include "kernel.h"
#include "vnode.h"
#include "specdev.h"
#include "mount.h"
#include "buf.h"
#include "file.h"
#include "dkbad.h"
#include "disklabel.h"
#include "ioctl.h"
#include "errno.h"
#include "malloc.h"

#include "iso.h"
#include "isofs_node.h"

extern int enodev ();

struct vfsops isofs_vfsops = {
       isofs_mount,
       isofs_start,
       isofs_unmount,
       isofs_root,
       (void *)enodev, /* quotactl */
       isofs_statfs,
       isofs_sync,
       isofs_fhtovp,
       isofs_vptofh,
       isofs_init
};

/*
* Called by vfs_mountroot when ufs is going to be mounted as root.
*
* Name is updated by mount(8) after booting.
*/
#define ROOTNAME        "root_device"

isofs_mountroot()
{
       register struct mount *mp;
       extern struct vnode *rootvp;
       struct proc *p = curproc;       /* XXX */
       struct iso_mnt *imp;
       register struct fs *fs;
       u_int size;
       int error;

       mp = (struct mount *)malloc((u_long)sizeof(struct mount),
               M_MOUNT, M_WAITOK);
       mp->mnt_op = &isofs_vfsops;
       mp->mnt_flag = MNT_RDONLY;
       mp->mnt_exroot = 0;
       mp->mnt_mounth = NULLVP;
       error = iso_mountfs(rootvp, mp, p);
       if (error) {
               free((caddr_t)mp, M_MOUNT);
               return (error);
       }
       if (error = vfs_lock(mp)) {
               (void)isofs_unmount(mp, 0, p);
               free((caddr_t)mp, M_MOUNT);
               return (error);
       }
       rootfs = mp;
       mp->mnt_next = mp;
       mp->mnt_prev = mp;
       mp->mnt_vnodecovered = NULLVP;
       imp = VFSTOISOFS(mp);
       bzero(imp->im_fsmnt, sizeof(imp->im_fsmnt));
       imp->im_fsmnt[0] = '/';
       bcopy((caddr_t)imp->im_fsmnt, (caddr_t)mp->mnt_stat.f_mntonname,
           MNAMELEN);
       (void) copystr(ROOTNAME, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
           &size);
       bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
       (void) isofs_statfs(mp, &mp->mnt_stat, p);
       vfs_unlock(mp);
       return (0);
}

/*
* Flag to allow forcible unmounting.
*/
int iso_doforce = 1;

/*
* VFS Operations.
*
* mount system call
*/
isofs_mount(mp, path, data, ndp, p)
       register struct mount *mp;
       char *path;
       caddr_t data;
       struct nameidata *ndp;
       struct proc *p;
{
       struct vnode *devvp;
       struct ufs_args args;
       u_int size;
       int error;
       struct iso_mnt *imp;

       if (error = copyin(data, (caddr_t)&args, sizeof (struct ufs_args)))
               return (error);

       if ((mp->mnt_flag & MNT_RDONLY) == 0)
               return (EROFS);

       /*
        * Process export requests.
        */
       if ((args.exflags & MNT_EXPORTED) || (mp->mnt_flag & MNT_EXPORTED)) {
               if (args.exflags & MNT_EXPORTED)
                       mp->mnt_flag |= MNT_EXPORTED;
               else
                       mp->mnt_flag &= ~MNT_EXPORTED;
               if (args.exflags & MNT_EXRDONLY)
                       mp->mnt_flag |= MNT_EXRDONLY;
               else
                       mp->mnt_flag &= ~MNT_EXRDONLY;
               mp->mnt_exroot = args.exroot;
       }
       /*
        * If updating, check whether changing from read-only to
        * read/write; if there is no device name, that's all we do.
        */
       if (mp->mnt_flag & MNT_UPDATE) {
               imp = VFSTOISOFS(mp);
               if (args.fspec == 0)
                       return (0);
       }
       /*
        * Not an update, or updating the name: look up the name
        * and verify that it refers to a sensible block device.
        */
       ndp->ni_nameiop = LOOKUP | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = args.fspec;
       if (error = namei(ndp, p))
               return (error);
       devvp = ndp->ni_vp;
       if (devvp->v_type != VBLK) {
               vrele(devvp);
               return (ENOTBLK);
       }
       if (major(devvp->v_rdev) >= nblkdev) {
               vrele(devvp);
               return (ENXIO);
       }

       if ((mp->mnt_flag & MNT_UPDATE) == 0)
               error = iso_mountfs(devvp, mp, p);
       else {
               if (devvp != imp->im_devvp)
                       error = EINVAL; /* needs translation */
               else
                       vrele(devvp);
       }
       if (error) {
               vrele(devvp);
               return (error);
       }
       imp = VFSTOISOFS(mp);
       (void) copyinstr(path, imp->im_fsmnt, sizeof(imp->im_fsmnt)-1, &size);
       bzero(imp->im_fsmnt + size, sizeof(imp->im_fsmnt) - size);
       bcopy((caddr_t)imp->im_fsmnt, (caddr_t)mp->mnt_stat.f_mntonname,
           MNAMELEN);
       (void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 
           &size);
       bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
       (void) isofs_statfs(mp, &mp->mnt_stat, p);
       return (0);
}

/*
* Common code for mount and mountroot
*/
iso_mountfs(devvp, mp, p)
       register struct vnode *devvp;
       struct mount *mp;
       struct proc *p;
{
       register struct iso_mnt *isomp = (struct iso_mnt *)0;
       struct buf *bp = NULL;
       dev_t dev = devvp->v_rdev;
       caddr_t base, space;
       int havepart = 0, blks;
       int error = EINVAL, i, size;
       int needclose = 0;
       int ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
       extern struct vnode *rootvp;
       int j;
       int iso_bsize;
       int iso_blknum;
       struct iso_volume_descriptor *vdp;
       struct iso_primary_descriptor *pri;
       struct iso_directory_record *rootp;
       int logical_block_size;

       if (!ronly)
               return (EROFS);

       /*
        * Disallow multiple mounts of the same device.
        * Disallow mounting of a device that is currently in use
        * (except for root, which might share swap device for miniroot).
        * Flush out any old buffers remaining from a previous use.
        */
       if (error = iso_mountedon(devvp))
               return (error);
       if (vcount(devvp) > 1 && devvp != rootvp)
               return (EBUSY);
       vinvalbuf(devvp, 1);
       if (error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, NOCRED, p))
               return (error);
       needclose = 1;

       /* This is the "logical sector size".  The standard says this
        * should be 2048 or the physical sector size on the device,
        * whichever is greater.  For now, we'll just use a constant.
        */
       iso_bsize = 2048;

       for (iso_blknum = 16; iso_blknum < 100; iso_blknum++) {
               if (error = bread (devvp, iso_blknum * iso_bsize / DEV_BSIZE,
                                  iso_bsize, NOCRED, &bp))
                       goto out;

               vdp = (struct iso_volume_descriptor *)bp->b_un.b_addr;
               if (bcmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) != 0) {
                       error = EINVAL;
                       goto out;
               }

               if (isonum_711 (vdp->type) == ISO_VD_END) {
                       error = EINVAL;
                       goto out;
               }

               if (isonum_711 (vdp->type) == ISO_VD_PRIMARY)
                       break;
               brelse(bp);
       }

       if (isonum_711 (vdp->type) != ISO_VD_PRIMARY) {
               error = EINVAL;
               goto out;
       }
       
       pri = (struct iso_primary_descriptor *)vdp;

       logical_block_size = isonum_723 (pri->logical_block_size);

       if (logical_block_size < DEV_BSIZE
           || logical_block_size >= MAXBSIZE
           || (logical_block_size & (logical_block_size - 1)) != 0) {
               error = EINVAL;
               goto out;
       }

       rootp = (struct iso_directory_record *)pri->root_directory_record;

       isomp = (struct iso_mnt *)malloc(sizeof *isomp,M_UFSMNT,M_WAITOK);
       isomp->logical_block_size = logical_block_size;
       isomp->volume_space_size = isonum_733 (pri->volume_space_size);
       bcopy (rootp, isomp->root, sizeof isomp->root);
       isomp->root_extent = isonum_733 (rootp->extent);
       isomp->root_size = isonum_733 (rootp->size);

       isomp->im_bsize = logical_block_size;
       isomp->im_bmask = ~(isomp->im_bsize - 1);
       isomp->im_bshift = 0;
       while ((1 << isomp->im_bshift) < isomp->im_bsize)
               isomp->im_bshift++;

       bp->b_flags |= B_INVAL;
       brelse(bp);
       bp = NULL;

       isomp->im_ronly = ronly;
       if (ronly == 0)
               isomp->im_fmod = 1;

       mp->mnt_data = (qaddr_t)isomp;
       mp->mnt_stat.f_fsid.val[0] = (long)dev;
       mp->mnt_stat.f_fsid.val[1] = MOUNT_ISOFS;
       mp->mnt_flag |= MNT_LOCAL;
       isomp->im_mountp = mp;
       isomp->im_dev = dev;
       isomp->im_devvp = devvp;

       devvp->v_specflags |= SI_MOUNTEDON;

       return (0);
out:
       if (bp)
               brelse(bp);
       if (needclose)
               (void)VOP_CLOSE(devvp, ronly ? FREAD : FREAD|FWRITE, NOCRED, p);
       if (isomp) {
               free((caddr_t)isomp, M_UFSMNT);
               mp->mnt_data = (qaddr_t)0;
       }
       return (error);
}

/*
* Make a filesystem operational.
* Nothing to do at the moment.
*/
/* ARGSUSED */
isofs_start(mp, flags, p)
       struct mount *mp;
       int flags;
       struct proc *p;
{

       return (0);
}

/*
* unmount system call
*/
isofs_unmount(mp, mntflags, p)
       struct mount *mp;
       int mntflags;
       struct proc *p;
{
       register struct iso_mnt *isomp;
       int i, error, ronly, flags = 0;

       if (mntflags & MNT_FORCE) {
               if (!iso_doforce || mp == rootfs)
                       return (EINVAL);
               flags |= FORCECLOSE;
       }
       mntflushbuf(mp, 0);
       if (mntinvalbuf(mp))
               return (EBUSY);
       isomp = VFSTOISOFS(mp);

       if (error = vflush(mp, NULLVP, flags))
               return (error);
       ronly = !isomp->im_ronly;
       isomp->im_devvp->v_specflags &= ~SI_MOUNTEDON;
       error = VOP_CLOSE(isomp->im_devvp, ronly ? FREAD : FREAD|FWRITE,
               NOCRED, p);
       vrele(isomp->im_devvp);
       free((caddr_t)isomp, M_UFSMNT);
       mp->mnt_data = (qaddr_t)0;
       mp->mnt_flag &= ~MNT_LOCAL;
       return (error);
}

/*
* Check to see if a filesystem is mounted on a block device.
*/
iso_mountedon(vp)
       register struct vnode *vp;
{
       register struct vnode *vq;

       if (vp->v_specflags & SI_MOUNTEDON)
               return (EBUSY);
       if (vp->v_flag & VALIASED) {
               for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
                       if (vq->v_rdev != vp->v_rdev ||
                           vq->v_type != vp->v_type)
                               continue;
                       if (vq->v_specflags & SI_MOUNTEDON)
                               return (EBUSY);
               }
       }
       return (0);
}

/*
* Return root of a filesystem
*/
isofs_root(mp, vpp)
       struct mount *mp;
       struct vnode **vpp;
{
       register struct iso_node *ip;
       struct iso_node *nip;
       struct vnode tvp;
       int error;
       struct iso_mnt *imp = VFSTOISOFS (mp);

       tvp.v_mount = mp;
       ip = VTOI(&tvp);
       ip->i_vnode = &tvp;
       ip->i_dev = imp->im_dev;
       error = iso_iget(ip, imp->root_extent, &nip,
                        (struct iso_directory_record *) imp->root);
       if (error)
               return (error);
       *vpp = ITOV(nip);
       return (0);
}

/*
* Get file system statistics.
*/
isofs_statfs(mp, sbp, p)
       struct mount *mp;
       register struct statfs *sbp;
       struct proc *p;
{
       register struct iso_mnt *isomp;
       register struct fs *fs;

       isomp = VFSTOISOFS(mp);

       sbp->f_type = MOUNT_ISOFS;
       sbp->f_fsize = isomp->logical_block_size;
       sbp->f_bsize = sbp->f_fsize;
       sbp->f_blocks = isomp->volume_space_size;
       sbp->f_bfree = 0; /* total free blocks */
       sbp->f_bavail = 0; /* blocks free for non superuser */
       sbp->f_files =  0; /* total files */
       sbp->f_ffree = 0; /* free file nodes */
       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);
}

isofs_sync(mp, waitfor)
       struct mount *mp;
       int waitfor;
{
       return (0);
}

/*
* File handle to vnode
*
* Have to be really careful about stale file handles:
* - check that the inode number is in range
* - call iget() to get the locked inode
* - check for an unallocated inode (i_mode == 0)
* - check that the generation number matches
*/
isofs_fhtovp(mp, fhp, vpp)
       register struct mount *mp;
       struct fid *fhp;
       struct vnode **vpp;
{
       return (EINVAL);
#if 0
       /* here's a guess at what we need here */
       struct vnode tvp;
       int error;

       ifhp = (struct ifid *)fhp;
       imp = VFSTOISOFS (mp);

       if (ifhp->ifid_lbn >= imp->volume_space_size)
               return (EINVAL);

       if (ifhp->ifid_offset + sizeof (struct iso_directory_record)
           >= imp->im_bsize)
               return (EINVAL);

       bread (isomp->im_devvp, ifhp->ifid_lbn, imp->im_bsize, NOCRED, &bp);

       dirp = bp->b_un.b_addr + ifhp->ifid_offset;

       if (ifhp->ifid_offset + isonum_711 (dirp) >= imp->im_bsize) {
               brelse (bp);
               return (EINVAL);
       }

       tvp.v_mount = mp;
       ip = VTOI(&tvp);
       ip->i_vnode = &tvp;
       ip->i_dev = imp->im_dev;
       if (error = iso_iget(ip, ifhp->ifid_ino, &nip, dirp)) {
               *vpp = NULLVP;
               brelse (bp);
               return (error);
       }
       ip = nip;
       *vpp = ITOV(ip);
       brelse (bp);
       return (0);
#endif
}

/*
* Vnode pointer to File handle
*/
/* ARGSUSED */
isofs_vptofh(vp, fhp)
       struct vnode *vp;
       struct fid *fhp;
{
       return (EINVAL);
#if 0
       register struct inode *ip = VTOI(vp);
       register struct ufid *ufhp;

       ufhp = (struct ufid *)fhp;
       ufhp->ufid_len = sizeof(struct ufid);
       ufhp->ufid_ino = ip->i_number;
       ufhp->ufid_gen = ip->i_gen;
       return (0);
#endif
}