NetBSD/sys/isofs/isofs_vfsops.c

/*
 *	$Id: isofs_vfsops.c,v 1.7 1993/09/07 15:41:00 ws Exp $
 */

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

static iso_mountfs();

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;
	struct iso_args args;

	mp = (struct mount *)malloc((u_long)sizeof(struct mount),
		M_MOUNT, M_WAITOK);
	mp->mnt_op = (struct vfsops *)&isofs_vfsops;
	mp->mnt_flag = MNT_RDONLY;
	mp->mnt_exroot = 0;
	mp->mnt_mounth = NULLVP;
	args.flags = ISOFSMNT_ROOT;
	error = iso_mountfs(rootvp, mp, p, &args);
	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 iso_args args;
	u_int size;
	int error;
	struct iso_mnt *imp;

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

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

	/*
	 * 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, &args);
	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
 */
static iso_mountfs(devvp, mp, p, argp)
	register struct vnode *devvp;
	struct mount *mp;
	struct proc *p;
	struct iso_args *argp;
{
	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 = 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_ISOFSMNT,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_AGE;
	brelse(bp);
	bp = NULL;

	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;

	/* Check the Rock Ridge Extention support */
	if (!(argp->flags & ISOFSMNT_NORRIP)) {
		if (error = bread (isomp->im_devvp,
				   (isomp->root_extent + isonum_711(rootp->ext_attr_length))
				   * isomp->im_bsize / DEV_BSIZE,
				   isomp->im_bsize,NOCRED,&bp))
		    goto out;
		
		rootp = (struct iso_directory_record *)bp->b_un.b_addr;
		
		if ((isomp->rr_skip = isofs_rrip_offset(rootp,isomp)) < 0) {
		    argp->flags  |= ISOFSMNT_NORRIP;
		} else {
		    argp->flags  &= ~ISOFSMNT_GENS;
		}
		
		/*
		 * The contents are valid,
		 * but they will get reread as part of another vnode, so...
		 */
		bp->b_flags |= B_AGE;
		brelse(bp);
		bp = NULL;
	}
	isomp->im_flags = argp->flags&(ISOFSMNT_NORRIP|ISOFSMNT_GENS|ISOFSMNT_EXTATT);
	switch (isomp->im_flags&(ISOFSMNT_NORRIP|ISOFSMNT_GENS)) {
	default:
	    isomp->iso_ftype = ISO_FTYPE_DEFAULT;
	    break;
	case ISOFSMNT_GENS|ISOFSMNT_NORRIP:
	    isomp->iso_ftype = ISO_FTYPE_9660;
	    break;
	case 0:
	    isomp->iso_ftype = ISO_FTYPE_RRIP;
	    break;
	}

	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_ISOFSMNT);
		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);
#ifdef	ISODEVMAP
	if (isomp->iso_ftype == ISO_FTYPE_RRIP)
		iso_dunmap(isomp->im_dev);
#endif
	
	isomp->im_devvp->v_specflags &= ~SI_MOUNTEDON;
	error = VOP_CLOSE(isomp->im_devvp, FREAD, NOCRED, p);
	vrele(isomp->im_devvp);
	free((caddr_t)isomp, M_ISOFSMNT);
	mp->mnt_data = (qaddr_t)0;
	mp->mnt_flag &= ~MNT_LOCAL;
	return (error);
}

/*
 * 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);
	struct iso_directory_record *dp;
	struct iso_directory_record dir;
	
	tvp.v_mount = mp;
	ip = VTOI(&tvp);
	ip->i_vnode = &tvp;
	ip->i_dev = imp->im_dev;
	ip->i_diroff = 0;
	dp = (struct iso_directory_record *) imp->root;
	isofs_defino(dp,&ip->i_number);
	/* If we have a rockridge CD, we must use the `.' dir entry */
	if (imp->iso_ftype == ISO_FTYPE_RRIP) {
	    /*
	     * With RRIP we must use the `.' entry of the root directory.
	     * Simply fake it with a different directory record,
	     * so iget thinks, it's a relocated directory.
	     */
	    dir = *dp;
	    dp = &dir;
	    bzero(dp->extent,sizeof(dp->extent));
	}
	error = iso_iget(ip, ip->i_number, &nip, dp);
	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);
	}
	/* Use the first spare for flags: */
	sbp->f_spare[0] = isomp->im_flags;
	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
 */


struct ifid {
	ushort	ifid_len;
	ushort	ifid_pad;
	int	ifid_parino;
	int	ifid_offset;
	int	ifid_ino;
};

isofs_fhtovp(mp, fhp, vpp)
	register struct mount *mp;
	struct fid *fhp;
	struct vnode **vpp;
{
	/* here's a guess at what we need here */
	struct vnode			tvp;
	int				error;
	int				lbn, off;
	struct ifid			*ifhp;
	struct iso_mnt			*imp;
	struct buf			*bp;
	struct iso_directory_record	*dirp;
	struct iso_node 		*ip, *nip;
	struct proc 			*p;
	ino_t				ino;
	char				altname[NAME_MAX];
	u_short				namelen;
	
	ifhp = (struct ifid *)fhp;
	imp = VFSTOISOFS (mp);

#ifdef	ISOFS_DBG
	printf("fhtovp: lbn %d, off %d, ino %d\n",
			ifhp->ifid_lbn, ifhp->ifid_offset, ifhp->ifid_ino);
#endif

	lbn = ifhp->ifid_parino;
	off = ifhp->ifid_offset;
	lbn += ifhp->ifid_offset / imp->im_bsize;
	off &= (imp->im_bsize - 1);

	if (lbn >= imp->volume_space_size) {
		printf("fhtovp: lbn exceed volume space %d\n",
			lbn );
		return (EINVAL);
	}

	if (off + ISO_DIRECTORY_RECORD_SIZE > imp->im_bsize) {
		printf("fhtovp: across the block boundary %d\n",
			off + ISO_DIRECTORY_RECORD_SIZE );
		return (EINVAL);
	}

	if (error = bread (imp->im_devvp,
		 (lbn * imp->im_bsize / DEV_BSIZE), imp->im_bsize, NOCRED, &bp)) {
		printf("fhtovp: bread error %d\n", error);
		brelse(bp);
		return(EINVAL);
	}

	dirp = (struct iso_directory_record *)(bp->b_un.b_addr + off);

	if (off + isonum_711 (dirp->length) > imp->im_bsize) {
		brelse (bp);
		printf("fhtovp: directory across the block boundary %d[off=%d/len=%d]\n",
			off + isonum_711(dirp->length), off, isonum_711(dirp->length) );
		return (EINVAL);
	}
	/* Isn't this a bit much for checking stale handles? */
	switch (imp->iso_ftype) {
	default:		/* ISO_FTYPE_9660 || ISO_FTYPE_DEFAULT */
	    isofs_defino(dirp,&ino);
	    break;
	case ISO_FTYPE_RRIP:
	    isofs_rrip_getname(dirp,altname,&namelen,&ino,imp);
	    break;
	}
	if (ino != ifhp->ifid_ino) {
		brelse(bp);
		printf("fhtovp: ino miss %d vs %d\n", ino, ifhp->ifid_ino );
		return(EINVAL);
	}

	tvp.v_mount = mp;
	ip = VTOI(&tvp);
	ip->i_vnode = &tvp;
	ip->i_dev = imp->im_dev;
	ip->i_diroff = ifhp->ifid_offset;
	ip->i_number = ifhp->ifid_parino;
	if (error = iso_iget(ip, ifhp->ifid_ino, &nip, dirp)) {
		*vpp = NULLVP;
		brelse (bp);
		printf("fhtovp: failed to get ino\n");
		return (error);
	}
	ip = nip;
	*vpp = ITOV(ip);
	brelse (bp);
	return (0);
}

/*
 * Vnode pointer to File handle
 */
/* ARGSUSED */
isofs_vptofh(vp, fhp)
	struct vnode *vp;
	struct fid *fhp;
{
	register struct iso_node *ip = VTOI(vp);
	register struct ifid *ifhp;
	register struct iso_mnt *mp = ip->i_mnt;

	ifhp = (struct ifid *)fhp;
	ifhp->ifid_len = sizeof(struct ifid);

	ifhp->ifid_parino = ip->iso_parent_ino;
	ifhp->ifid_offset = ip->iso_parent;
	ifhp->ifid_ino = ip->i_number;

#ifdef	ISOFS_DBG
	printf("vptofh: lbn %d, off %d, ino %d\n",
			ifhp->ifid_parino, ifhp->ifid_offset, ifhp->ifid_ino);
#endif
	return (0);
}