xref: /src/sys/coda/coda_venus.c

/*	$NetBSD: coda_venus.c,v 1.31 2024/05/17 23:57:46 thorpej Exp $	*/

/*
 *
 *             Coda: an Experimental Distributed File System
 *                              Release 3.1
 *
 *           Copyright (c) 1987-1998 Carnegie Mellon University
 *                          All Rights Reserved
 *
 * Permission  to  use, copy, modify and distribute this software and its
 * documentation is hereby granted,  provided  that  both  the  copyright
 * notice  and  this  permission  notice  appear  in  all  copies  of the
 * software, derivative works or  modified  versions,  and  any  portions
 * thereof, and that both notices appear in supporting documentation, and
 * that credit is given to Carnegie Mellon University  in  all  documents
 * and publicity pertaining to direct or indirect use of this code or its
 * derivatives.
 *
 * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
 * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
 * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
 * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
 * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
 * ANY DERIVATIVE WORK.
 *
 * Carnegie  Mellon  encourages  users  of  this  software  to return any
 * improvements or extensions that  they  make,  and  to  grant  Carnegie
 * Mellon the rights to redistribute these changes without encumbrance.
 *
 * 	@(#) coda/coda_venus.c,v 1.1.1.1 1998/08/29 21:26:45 rvb Exp $
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: coda_venus.c,v 1.31 2024/05/17 23:57:46 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/select.h>
#include <sys/ioctl.h>
/* for CNV_OFLAGS below */
#include <sys/fcntl.h>
#include <sys/kauth.h>

#include <coda/coda.h>
#include <coda/cnode.h>
#include <coda/coda_venus.h>
#include <coda/coda_pioctl.h>

#ifdef _KERNEL_OPT
#include "opt_coda_compat.h"
#endif

/*
 * Isize and Osize are the sizes of the input and output arguments.
 * SEMI-INVARIANT: name##_size (e.g. coda_readlink_size) is the max of
 * the input and output.  This invariant is not well maintained, but
 * should be true after ALLOC_*.  Isize is modified after allocation
 * by STRCPY below - this is in general unsafe and needs fixing.
 */

#define DECL_NO_IN(name) 				\
    struct coda_in_hdr *inp;				\
    struct name ## _out *outp;				\
    int name ## _size = sizeof (struct coda_in_hdr);	\
    int Isize = sizeof (struct coda_in_hdr);		\
    int Osize = sizeof (struct name ## _out);		\
    int error

#define DECL(name)					\
    struct name ## _in *inp;				\
    struct name ## _out *outp;				\
    int name ## _size = sizeof (struct name ## _in);	\
    int Isize = sizeof (struct name ## _in);		\
    int Osize = sizeof (struct name ## _out);		\
    int error

#define DECL_NO_OUT(name)				\
    struct name ## _in *inp;				\
    int name ## _size = sizeof (struct name ## _in);	\
    int Isize = sizeof (struct name ## _in);		\
    int Osize = sizeof (struct coda_out_hdr);		\
    int error

#define ALLOC_NO_IN(name)				\
    if (Osize > name ## _size)				\
    	name ## _size = Osize;				\
    CODA_ALLOC(inp, struct coda_in_hdr *, name ## _size);\
    outp = (struct name ## _out *) inp

#define ALLOC(name)					\
    if (Osize > name ## _size)				\
    	name ## _size = Osize;				\
    CODA_ALLOC(inp, struct name ## _in *, name ## _size);\
    outp = (struct name ## _out *) inp

#define ALLOC_NO_OUT(name)				\
    if (Osize > name ## _size)				\
    	name ## _size = Osize;				\
    CODA_ALLOC(inp, struct name ## _in *, name ## _size);\

#define STRCPY(struc, name, len) \
    memcpy((char *)inp + (int)inp->struc, name, len); \
    ((char*)inp + (int)inp->struc)[len++] = 0; \
    Isize += len
/* XXX verify that Isize has not overrun available storage */

#ifdef CODA_COMPAT_5

#define INIT_IN(in, op, ident, p) \
	  (in)->opcode = (op); \
	  (in)->pid = p ? p->p_pid : -1; \
          (in)->pgid = p ? p->p_pgid : -1; \
          (in)->sid = (p && p->p_session && p->p_session->s_leader) ? \
		(p->p_session->s_leader->p_pid) : -1; \
	  KASSERT(cred != NULL); \
	  KASSERT(cred != FSCRED); \
          if (ident != NOCRED) {                              \
	      (in)->cred.cr_uid = kauth_cred_geteuid(ident);              \
	      (in)->cred.cr_groupid = kauth_cred_getegid(ident);          \
          } else {                                            \
	      memset(&((in)->cred), 0, sizeof(struct coda_cred)); \
	      (in)->cred.cr_uid = -1;                         \
	      (in)->cred.cr_groupid = -1;                     \
          }                                                   \

#else

#define INIT_IN(in, op, ident, p) 		\
	  (in)->opcode = (op); 			\
	  (in)->pid = p ? p->p_pid : -1;        \
          (in)->pgid = p ? p->p_pgid : -1;	\
	  KASSERT(cred != NULL); \
	  KASSERT(cred != FSCRED); \
          if (ident != NOCRED) {                \
	      (in)->uid = kauth_cred_geteuid(ident);        \
          } else {                              \
	      (in)->uid = -1;                   \
          }                                                   \

#endif

#define INIT_IN_L(in, op, ident, l)		\
	INIT_IN(in, op, ident, (l ? l->l_proc : NULL))

#define	CNV_OFLAG(to, from) 				\
    do { 						\
	  to = 0;					\
	  if (from & FREAD)   to |= C_O_READ; 		\
	  if (from & FWRITE)  to |= C_O_WRITE; 		\
	  if (from & O_TRUNC) to |= C_O_TRUNC; 		\
	  if (from & O_EXCL)  to |= C_O_EXCL; 		\
	  if (from & O_CREAT) to |= C_O_CREAT;		\
    } while (/*CONSTCOND*/ 0)

#define CNV_VV2V_ATTR(top, fromp) \
	do { \
		(top)->va_type = (fromp)->va_type; \
		(top)->va_mode = (fromp)->va_mode; \
		(top)->va_nlink = (fromp)->va_nlink; \
		(top)->va_uid = (fromp)->va_uid; \
		(top)->va_gid = (fromp)->va_gid; \
		(top)->va_fsid = VNOVAL; \
		(top)->va_fileid = (fromp)->va_fileid; \
		(top)->va_size = (fromp)->va_size; \
		(top)->va_blocksize = (fromp)->va_blocksize; \
		(top)->va_atime = (fromp)->va_atime; \
		(top)->va_mtime = (fromp)->va_mtime; \
		(top)->va_ctime = (fromp)->va_ctime; \
		(top)->va_gen = (fromp)->va_gen; \
		(top)->va_flags = (fromp)->va_flags; \
		(top)->va_rdev = (fromp)->va_rdev; \
		(top)->va_bytes = (fromp)->va_bytes; \
		(top)->va_filerev = (fromp)->va_filerev; \
		(top)->va_vaflags = VNOVAL; \
		(top)->va_spare = VNOVAL; \
	} while (/*CONSTCOND*/ 0)

#define CNV_V2VV_ATTR(top, fromp) \
	do { \
		(top)->va_type = (fromp)->va_type; \
		(top)->va_mode = (fromp)->va_mode; \
		(top)->va_nlink = (fromp)->va_nlink; \
		(top)->va_uid = (fromp)->va_uid; \
		(top)->va_gid = (fromp)->va_gid; \
		(top)->va_fileid = (fromp)->va_fileid; \
		(top)->va_size = (fromp)->va_size; \
		(top)->va_blocksize = (fromp)->va_blocksize; \
		(top)->va_atime = (fromp)->va_atime; \
		(top)->va_mtime = (fromp)->va_mtime; \
		(top)->va_ctime = (fromp)->va_ctime; \
		(top)->va_gen = (fromp)->va_gen; \
		(top)->va_flags = (fromp)->va_flags; \
		(top)->va_rdev = (fromp)->va_rdev; \
		(top)->va_bytes = (fromp)->va_bytes; \
		(top)->va_filerev = (fromp)->va_filerev; \
	} while (/*CONSTCOND*/ 0)


int
venus_root(void *mdp,
	kauth_cred_t cred, struct proc *p,
/*out*/	CodaFid *VFid)
{
    DECL_NO_IN(coda_root);		/* sets Isize & Osize */
    ALLOC_NO_IN(coda_root);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN(inp, CODA_ROOT, cred, p);

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    if (!error)
	*VFid = outp->Fid;

    CODA_FREE(inp, coda_root_size);
    return error;
}

int
venus_open(void *mdp, CodaFid *fid, int flag,
	kauth_cred_t cred, struct lwp *l,
/*out*/	dev_t *dev, ino_t *inode)
{
    int cflag;
    DECL(coda_open);			/* sets Isize & Osize */
    ALLOC(coda_open);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_OPEN, cred, l);
    inp->Fid = *fid;
    CNV_OFLAG(cflag, flag);
    inp->flags = cflag;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	*dev =  outp->dev;
	*inode = outp->inode;
    }

    CODA_FREE(inp, coda_open_size);
    return error;
}

int
venus_close(void *mdp, CodaFid *fid, int flag,
	kauth_cred_t cred, struct lwp *l)
{
    int cflag;
    DECL_NO_OUT(coda_close);		/* sets Isize & Osize */
    ALLOC_NO_OUT(coda_close);		/* sets inp & outp */

    INIT_IN_L(&inp->ih, CODA_CLOSE, cred, l);
    inp->Fid = *fid;
    CNV_OFLAG(cflag, flag);
    inp->flags = cflag;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_close_size);
    return error;
}

/*
 * these two calls will not exist!!!  the container file is read/written
 * directly.
 */
void
venus_read(void)
{
}

void
venus_write(void)
{
}

/*
 * this is a bit sad too.  the ioctl's are for the control file, not for
 * normal files.
 */
int
venus_ioctl(void *mdp, CodaFid *fid,
	int com, int flag, void *data,
	kauth_cred_t cred, struct lwp *l)
{
    DECL(coda_ioctl);			/* sets Isize & Osize */
    struct PioctlData *iap = (struct PioctlData *)data;
    int tmp;

    coda_ioctl_size = VC_MAXMSGSIZE;
    ALLOC(coda_ioctl);			/* sets inp & outp */

    INIT_IN_L(&inp->ih, CODA_IOCTL, cred, l);
    inp->Fid = *fid;

    /* command was mutated by increasing its size field to reflect the
     * path and follow args. we need to subtract that out before sending
     * the command to venus.
     */
    inp->cmd = (com & ~(IOCPARM_MASK << 16));
    tmp = ((com >> 16) & IOCPARM_MASK) - sizeof (char *) - sizeof (int);
    inp->cmd |= (tmp & IOCPARM_MASK) <<	16;

    if (iap->vi.in_size > VC_MAXMSGSIZE || iap->vi.out_size > VC_MAXMSGSIZE) {
	CODA_FREE(inp, coda_ioctl_size);
	return (EINVAL);
    }

    inp->rwflag = flag;
    inp->len = iap->vi.in_size;
    inp->data = (char *)(sizeof (struct coda_ioctl_in));

    error = copyin(iap->vi.in, (char*)inp + (int)(long)inp->data,
		   iap->vi.in_size);
    if (error) {
	CODA_FREE(inp, coda_ioctl_size);
	return(error);
    }

    Osize = VC_MAXMSGSIZE;
    error = coda_call(mdp, Isize + iap->vi.in_size, &Osize, (char *)inp);

	/* copy out the out buffer. */
    if (!error) {
	if (outp->len > iap->vi.out_size) {
	    error = EINVAL;
	} else {
	    error = copyout((char *)outp + (int)(long)outp->data,
			    iap->vi.out, iap->vi.out_size);
	}
    }

    CODA_FREE(inp, coda_ioctl_size);
    return error;
}

int
venus_getattr(void *mdp, CodaFid *fid,
	kauth_cred_t cred, struct lwp *l,
/*out*/	struct vattr *vap)
{
    DECL(coda_getattr);			/* sets Isize & Osize */
    ALLOC(coda_getattr);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_GETATTR, cred, l);
    inp->Fid = *fid;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    if (!error) {
	CNV_VV2V_ATTR(vap, &outp->attr);
    }

    CODA_FREE(inp, coda_getattr_size);
    return error;
}

int
venus_setattr(void *mdp, CodaFid *fid, struct vattr *vap,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_setattr);		/* sets Isize & Osize */
    ALLOC_NO_OUT(coda_setattr);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_SETATTR, cred, l);
    inp->Fid = *fid;
    CNV_V2VV_ATTR(&inp->attr, vap);

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_setattr_size);
    return error;
}

int
venus_access(void *mdp, CodaFid *fid, int mode,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_access);		/* sets Isize & Osize */
    ALLOC_NO_OUT(coda_access);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_ACCESS, cred, l);
    inp->Fid = *fid;
    inp->flags = mode;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_access_size);
    return error;
}

int
venus_readlink(void *mdp, CodaFid *fid,
	kauth_cred_t cred, struct lwp *l,
/*out*/	char **str, int *len)
{
    DECL(coda_readlink);			/* sets Isize & Osize */
    /* XXX coda_readlink_size should not be set here */
    coda_readlink_size += CODA_MAXPATHLEN;
    Osize += CODA_MAXPATHLEN;
    ALLOC(coda_readlink);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_READLINK, cred, l);
    inp->Fid = *fid;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (error != 0)
	    goto out;

    /* Check count for reasonableness */
    if (outp->count <= 0 || outp->count > CODA_MAXPATHLEN) {
	    printf("venus_readlink: bad count %d\n", outp->count);
	    error = EINVAL;
	    goto out;
    }

    /*
     * Check data pointer for reasonableness.  It must point after
     * itself, and within the allocated region.
     */
    if ((intptr_t) outp->data < sizeof(struct coda_readlink_out) ) {
	    printf("venus_readlink: data pointer %lld too low\n",
		   (long long)((intptr_t) outp->data));
	    error = EINVAL;
	    goto out;
    }

    if ((intptr_t) outp->data + outp->count >
	sizeof(struct coda_readlink_out) + CODA_MAXPATHLEN) {
	    printf("venus_readlink: data pointer %lld too high\n",
		   (long long)((intptr_t) outp->data));
	    error = EINVAL;
	    goto out;
    }

    if (!error) {
	    CODA_ALLOC(*str, char *, outp->count);
	    *len = outp->count;
	    memcpy(*str, (char *)outp + (int)(long)outp->data, *len);
    }

out:
    CODA_FREE(inp, coda_readlink_size);
    return error;
}

int
venus_fsync(void *mdp, CodaFid *fid,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_fsync);		/* sets Isize & Osize */
    ALLOC_NO_OUT(coda_fsync);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_FSYNC, cred, l);
    inp->Fid = *fid;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_fsync_size);
    return error;
}

int
venus_lookup(void *mdp, CodaFid *fid,
    	const char *nm, int len,
	kauth_cred_t cred, struct lwp *l,
/*out*/	CodaFid *VFid, int *vtype)
{
    DECL(coda_lookup);			/* sets Isize & Osize */
    coda_lookup_size += len + 1;
    ALLOC(coda_lookup);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_LOOKUP, cred, l);
    inp->Fid = *fid;

    /* NOTE:
     * Between version 1 and version 2 we have added an extra flag field
     * to this structure.  But because the string was at the end and because
     * of the weird way we represent strings by having the slot point to
     * where the string characters are in the "heap", we can just slip the
     * flag parameter in after the string slot pointer and veni that don't
     * know better won't see this new flag field ...
     * Otherwise we'd need two different venus_lookup functions.
     */
    inp->name = Isize;
    inp->flags = CLU_CASE_SENSITIVE;	/* doesn't really matter for BSD */
    /* This is safe because we preallocated len+1 extra. */
    STRCPY(name, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	*VFid = outp->Fid;
	*vtype = outp->vtype;
    }

    CODA_FREE(inp, coda_lookup_size);
    return error;
}

int
venus_create(void *mdp, CodaFid *fid,
    	const char *nm, int len, int exclusive, int mode, struct vattr *va,
	kauth_cred_t cred, struct lwp *l,
/*out*/	CodaFid *VFid, struct vattr *attr)
{
    DECL(coda_create);			/* sets Isize & Osize */
    coda_create_size += len + 1;
    ALLOC(coda_create);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_CREATE, cred, l);
    inp->Fid = *fid;
    inp->excl = exclusive ? C_O_EXCL : 0;
    inp->mode = mode<<6;
    CNV_V2VV_ATTR(&inp->attr, va);

    inp->name = Isize;
    STRCPY(name, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	*VFid = outp->Fid;
	CNV_VV2V_ATTR(attr, &outp->attr);
    }

    CODA_FREE(inp, coda_create_size);
    return error;
}

int
venus_remove(void *mdp, CodaFid *fid,
        const char *nm, int len,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_remove);		/* sets Isize & Osize */
    coda_remove_size += len + 1;
    ALLOC_NO_OUT(coda_remove);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_REMOVE, cred, l);
    inp->Fid = *fid;

    inp->name = Isize;
    STRCPY(name, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_remove_size);
    return error;
}

int
venus_link(void *mdp, CodaFid *fid, CodaFid *tfid,
        const char *nm, int len,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_link);		/* sets Isize & Osize */
    coda_link_size += len + 1;
    ALLOC_NO_OUT(coda_link);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_LINK, cred, l);
    inp->sourceFid = *fid;
    inp->destFid = *tfid;

    inp->tname = Isize;
    STRCPY(tname, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_link_size);
    return error;
}

int
venus_rename(void *mdp, CodaFid *fid, CodaFid *tfid,
        const char *nm, int len, const char *tnm, int tlen,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_rename);		/* sets Isize & Osize */
    coda_rename_size += len + 1 + tlen + 1;
    ALLOC_NO_OUT(coda_rename);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_RENAME, cred, l);
    inp->sourceFid = *fid;
    inp->destFid = *tfid;

    inp->srcname = Isize;
    STRCPY(srcname, nm, len);		/* increments Isize */

    inp->destname = Isize;
    STRCPY(destname, tnm, tlen);	/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_rename_size);
    return error;
}

int
venus_mkdir(void *mdp, CodaFid *fid,
    	const char *nm, int len, struct vattr *va,
	kauth_cred_t cred, struct lwp *l,
/*out*/	CodaFid *VFid, struct vattr *ova)
{
    DECL(coda_mkdir);			/* sets Isize & Osize */
    coda_mkdir_size += len + 1;
    ALLOC(coda_mkdir);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_MKDIR, cred, l);
    inp->Fid = *fid;
    CNV_V2VV_ATTR(&inp->attr, va);

    inp->name = Isize;
    STRCPY(name, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	*VFid = outp->Fid;
	CNV_VV2V_ATTR(ova, &outp->attr);
    }

    CODA_FREE(inp, coda_mkdir_size);
    return error;
}

int
venus_rmdir(void *mdp, CodaFid *fid,
    	const char *nm, int len,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_rmdir);		/* sets Isize & Osize */
    coda_rmdir_size += len + 1;
    ALLOC_NO_OUT(coda_rmdir);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_RMDIR, cred, l);
    inp->Fid = *fid;

    inp->name = Isize;
    STRCPY(name, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_rmdir_size);
    return error;
}

int
venus_symlink(void *mdp, CodaFid *fid,
        const char *lnm, int llen, const char *nm, int len, struct vattr *va,
	kauth_cred_t cred, struct lwp *l)
{
    DECL_NO_OUT(coda_symlink);		/* sets Isize & Osize */
    coda_symlink_size += llen + 1 + len + 1;
    ALLOC_NO_OUT(coda_symlink);		/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_SYMLINK, cred, l);
    inp->Fid = *fid;
    CNV_V2VV_ATTR(&inp->attr, va);

    inp->srcname = Isize;
    STRCPY(srcname, lnm, llen);		/* increments Isize */

    inp->tname = Isize;
    STRCPY(tname, nm, len);		/* increments Isize */

    error = coda_call(mdp, Isize, &Osize, (char *)inp);

    CODA_FREE(inp, coda_symlink_size);
    return error;
}

int
venus_readdir(void *mdp, CodaFid *fid,
    	int count, int offset,
	kauth_cred_t cred, struct lwp *l,
/*out*/	char *buffer, int *len)
{
    DECL(coda_readdir);			/* sets Isize & Osize */
    coda_readdir_size = VC_MAXMSGSIZE;
    ALLOC(coda_readdir);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_READDIR, cred, l);
    inp->Fid = *fid;
    inp->count = count;
    inp->offset = offset;

    Osize = VC_MAXMSGSIZE;
    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	memcpy(buffer, (char *)outp + (int)(long)outp->data, outp->size);
	*len = outp->size;
    }

    CODA_FREE(inp, coda_readdir_size);
    return error;
}

int
venus_statfs(void *mdp, kauth_cred_t cred, struct lwp *l,
   /*out*/   struct coda_statfs *fsp)
{
    DECL(coda_statfs);			/* sets Isize & Osize */
    ALLOC(coda_statfs);			/* sets inp & outp */

    /* send the open to venus. */
    INIT_IN_L(&inp->ih, CODA_STATFS, cred, l);

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
        *fsp = outp->stat;
    }

    CODA_FREE(inp, coda_statfs_size);
    return error;
}

int
venus_fhtovp(void *mdp, CodaFid *fid,
	kauth_cred_t cred, struct proc *p,
/*out*/	CodaFid *VFid, int *vtype)
{
    DECL(coda_vget);			/* sets Isize & Osize */
    ALLOC(coda_vget);			/* sets inp & outp */

    /* Send the open to Venus. */
    INIT_IN(&inp->ih, CODA_VGET, cred, p);
    inp->Fid = *fid;

    error = coda_call(mdp, Isize, &Osize, (char *)inp);
    KASSERT(outp != NULL);
    if (!error) {
	*VFid = outp->Fid;
	*vtype = outp->vtype;
    }

    CODA_FREE(inp, coda_vget_size);
    return error;
}