/*

   *  Server-side procedures for NFSv4.
   *
   *  Copyright (c) 2002 The Regents of the University of Michigan.
   *  All rights reserved.
   *
   *  Kendrick Smith <kmsmith@umich.edu>
   *  Andy Adamson   <andros@umich.edu>
   *
   *  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. 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 ``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.

   */

  #include <linux/file.h>

  #include <linux/slab.h>

  #include "idmap.h"

  #include "cache.h"
  #include "xdr4.h"

  #include "vfs.h"

  
  #define NFSDDBG_FACILITY		NFSDDBG_PROC

  static u32 nfsd_attrmask[] = {
  	NFSD_WRITEABLE_ATTRS_WORD0,
  	NFSD_WRITEABLE_ATTRS_WORD1,
  	NFSD_WRITEABLE_ATTRS_WORD2
  };
  
  static u32 nfsd41_ex_attrmask[] = {
  	NFSD_SUPPATTR_EXCLCREAT_WORD0,
  	NFSD_SUPPATTR_EXCLCREAT_WORD1,
  	NFSD_SUPPATTR_EXCLCREAT_WORD2
  };
  
  static __be32
  check_attr_support(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  		   u32 *bmval, u32 *writable)
  {
  	struct dentry *dentry = cstate->current_fh.fh_dentry;

  
  	/*
  	 * Check about attributes are supported by the NFSv4 server or not.
  	 * According to spec, unsupported attributes return ERR_ATTRNOTSUPP.
  	 */
  	if ((bmval[0] & ~nfsd_suppattrs0(cstate->minorversion)) ||
  	    (bmval[1] & ~nfsd_suppattrs1(cstate->minorversion)) ||
  	    (bmval[2] & ~nfsd_suppattrs2(cstate->minorversion)))
  		return nfserr_attrnotsupp;
  
  	/*

  	 * Check FATTR4_WORD0_ACL can be supported

  	 * in current environment or not.
  	 */
  	if (bmval[0] & FATTR4_WORD0_ACL) {
  		if (!IS_POSIXACL(dentry->d_inode))
  			return nfserr_attrnotsupp;
  	}

  
  	/*
  	 * According to spec, read-only attributes return ERR_INVAL.
  	 */
  	if (writable) {
  		if ((bmval[0] & ~writable[0]) || (bmval[1] & ~writable[1]) ||
  		    (bmval[2] & ~writable[2]))
  			return nfserr_inval;
  	}
  
  	return nfs_ok;
  }
  
  static __be32
  nfsd4_check_open_attributes(struct svc_rqst *rqstp,
  	struct nfsd4_compound_state *cstate, struct nfsd4_open *open)
  {
  	__be32 status = nfs_ok;
  
  	if (open->op_create == NFS4_OPEN_CREATE) {
  		if (open->op_createmode == NFS4_CREATE_UNCHECKED
  		    || open->op_createmode == NFS4_CREATE_GUARDED)
  			status = check_attr_support(rqstp, cstate,
  					open->op_bmval, nfsd_attrmask);
  		else if (open->op_createmode == NFS4_CREATE_EXCLUSIVE4_1)
  			status = check_attr_support(rqstp, cstate,
  					open->op_bmval, nfsd41_ex_attrmask);
  	}
  
  	return status;
  }

  static int
  is_create_with_attrs(struct nfsd4_open *open)
  {
  	return open->op_create == NFS4_OPEN_CREATE
  		&& (open->op_createmode == NFS4_CREATE_UNCHECKED
  		    || open->op_createmode == NFS4_CREATE_GUARDED
  		    || open->op_createmode == NFS4_CREATE_EXCLUSIVE4_1);
  }
  
  /*
   * if error occurs when setting the acl, just clear the acl bit
   * in the returned attr bitmap.
   */
  static void
  do_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
  		struct nfs4_acl *acl, u32 *bmval)
  {
  	__be32 status;
  
  	status = nfsd4_set_nfs4_acl(rqstp, fhp, acl);
  	if (status)
  		/*
  		 * We should probably fail the whole open at this point,
  		 * but we've already created the file, so it's too late;
  		 * So this seems the least of evils:
  		 */
  		bmval[0] &= ~FATTR4_WORD0_ACL;
  }

  static inline void
  fh_dup2(struct svc_fh *dst, struct svc_fh *src)
  {
  	fh_put(dst);
  	dget(src->fh_dentry);
  	if (src->fh_export)
  		cache_get(&src->fh_export->h);
  	*dst = *src;
  }

  static __be32

  do_open_permission(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open, int accmode)

  {

  	__be32 status;

  
  	if (open->op_truncate &&
  		!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
  		return nfserr_inval;

  	accmode |= NFSD_MAY_READ_IF_EXEC;

  	if (open->op_share_access & NFS4_SHARE_ACCESS_READ)

  		accmode |= NFSD_MAY_READ;

  	if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)

  		accmode |= (NFSD_MAY_WRITE | NFSD_MAY_TRUNC);

  	if (open->op_share_deny & NFS4_SHARE_DENY_READ)

  		accmode |= NFSD_MAY_WRITE;

  
  	status = fh_verify(rqstp, current_fh, S_IFREG, accmode);
  
  	return status;
  }

  static __be32 nfsd_check_obj_isreg(struct svc_fh *fh)
  {
  	umode_t mode = fh->fh_dentry->d_inode->i_mode;
  
  	if (S_ISREG(mode))
  		return nfs_ok;
  	if (S_ISDIR(mode))
  		return nfserr_isdir;
  	/*
  	 * Using err_symlink as our catch-all case may look odd; but
  	 * there's no other obvious error for this case in 4.0, and we
  	 * happen to know that it will cause the linux v4 client to do
  	 * the right thing on attempts to open something other than a
  	 * regular file.
  	 */
  	return nfserr_symlink;
  }

  static __be32

  do_open_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
  {
  	struct svc_fh resfh;

  	__be32 status;

  
  	fh_init(&resfh, NFS4_FHSIZE);
  	open->op_truncate = 0;
  
  	if (open->op_create) {

  		/* FIXME: check session persistence and pnfs flags.
  		 * The nfsv4.1 spec requires the following semantics:
  		 *
  		 * Persistent   | pNFS   | Server REQUIRED | Client Allowed
  		 * Reply Cache  | server |                 |
  		 * -------------+--------+-----------------+--------------------
  		 * no           | no     | EXCLUSIVE4_1    | EXCLUSIVE4_1
  		 *              |        |                 | (SHOULD)
  		 *              |        | and EXCLUSIVE4  | or EXCLUSIVE4
  		 *              |        |                 | (SHOULD NOT)
  		 * no           | yes    | EXCLUSIVE4_1    | EXCLUSIVE4_1
  		 * yes          | no     | GUARDED4        | GUARDED4
  		 * yes          | yes    | GUARDED4        | GUARDED4
  		 */

  		/*
  		 * Note: create modes (UNCHECKED,GUARDED...) are the same

  		 * in NFSv4 as in v3 except EXCLUSIVE4_1.

  		 */

  		status = do_nfsd_create(rqstp, current_fh, open->op_fname.data,

  					open->op_fname.len, &open->op_iattr,
  					&resfh, open->op_createmode,

  					(u32 *)open->op_verf.data,

  					&open->op_truncate, &open->op_created);

  		/*
  		 * Following rfc 3530 14.2.16, use the returned bitmask
  		 * to indicate which attributes we used to store the
  		 * verifier:

  		 */
  		if (open->op_createmode == NFS4_CREATE_EXCLUSIVE && status == 0)

  			open->op_bmval[1] = (FATTR4_WORD1_TIME_ACCESS |

  						FATTR4_WORD1_TIME_MODIFY);

  	} else {

  		status = nfsd_lookup(rqstp, current_fh,
  				     open->op_fname.data, open->op_fname.len, &resfh);
  		fh_unlock(current_fh);

  		if (status)
  			goto out;
  		status = nfsd_check_obj_isreg(&resfh);

  	}

  	if (status)
  		goto out;

  	if (is_create_with_attrs(open) && open->op_acl != NULL)
  		do_set_nfs4_acl(rqstp, &resfh, open->op_acl, open->op_bmval);

  	set_change_info(&open->op_cinfo, current_fh);

  	fh_dup2(current_fh, &resfh);

  	/* set reply cache */

  	fh_copy_shallow(&open->op_openowner->oo_owner.so_replay.rp_openfh,

  			&resfh.fh_handle);

  	if (!open->op_created)

  		status = do_open_permission(rqstp, current_fh, open,
  					    NFSD_MAY_NOP);

  out:

  	fh_put(&resfh);
  	return status;
  }

  static __be32

  do_open_fhandle(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
  {

  	__be32 status;

  	/* We don't know the target directory, and therefore can not
  	* set the change info
  	*/
  
  	memset(&open->op_cinfo, 0, sizeof(struct nfsd4_change_info));
  
  	/* set replay cache */

  	fh_copy_shallow(&open->op_openowner->oo_owner.so_replay.rp_openfh,

  			&current_fh->fh_handle);

  
  	open->op_truncate = (open->op_iattr.ia_valid & ATTR_SIZE) &&
  		(open->op_iattr.ia_size == 0);

  	status = do_open_permission(rqstp, current_fh, open,
  				    NFSD_MAY_OWNER_OVERRIDE);

  
  	return status;
  }

  static void
  copy_clientid(clientid_t *clid, struct nfsd4_session *session)
  {
  	struct nfsd4_sessionid *sid =
  			(struct nfsd4_sessionid *)session->se_sessionid.data;
  
  	clid->cl_boot = sid->clientid.cl_boot;
  	clid->cl_id = sid->clientid.cl_id;
  }

  static __be32

  nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,

  	   struct nfsd4_open *open)

  {

  	__be32 status;

  	struct nfsd4_compoundres *resp;

  	dprintk("NFSD: nfsd4_open filename %.*s op_openowner %p
  ",

  		(int)open->op_fname.len, open->op_fname.data,

  		open->op_openowner);

  	/* This check required by spec. */
  	if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL)
  		return nfserr_inval;

  	/* We don't yet support WANT bits: */
  	open->op_share_access &= NFS4_SHARE_ACCESS_MASK;

  	open->op_created = 0;

  	/*
  	 * RFC5661 18.51.3
  	 * Before RECLAIM_COMPLETE done, server should deny new lock
  	 */
  	if (nfsd4_has_session(cstate) &&
  	    !cstate->session->se_client->cl_firststate &&
  	    open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS)
  		return nfserr_grace;

  	if (nfsd4_has_session(cstate))
  		copy_clientid(&open->op_clientid, cstate->session);

  	nfs4_lock_state();
  
  	/* check seqid for replay. set nfs4_owner */

  	resp = rqstp->rq_resp;
  	status = nfsd4_process_open1(&resp->cstate, open);

  	if (status == nfserr_replay_me) {

  		struct nfs4_replay *rp = &open->op_openowner->oo_owner.so_replay;

  		fh_put(&cstate->current_fh);

  		fh_copy_shallow(&cstate->current_fh.fh_handle,
  				&rp->rp_openfh);

  		status = fh_verify(rqstp, &cstate->current_fh, 0, NFSD_MAY_NOP);

  		if (status)
  			dprintk("nfsd4_open: replay failed"
  				" restoring previous filehandle
  ");
  		else

  			status = nfserr_replay_me;

  	}
  	if (status)
  		goto out;

  	status = nfsd4_check_open_attributes(rqstp, cstate, open);
  	if (status)
  		goto out;

  	/* Openowner is now set, so sequence id will get bumped.  Now we need
  	 * these checks before we do any creates: */

  	status = nfserr_grace;

  	if (locks_in_grace() && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS)

  		goto out;
  	status = nfserr_no_grace;

  	if (!locks_in_grace() && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)

  		goto out;

  	switch (open->op_claim_type) {

  		case NFS4_OPEN_CLAIM_DELEGATE_CUR:

  		case NFS4_OPEN_CLAIM_NULL:

  			status = do_open_lookup(rqstp, &cstate->current_fh,
  						open);

  			if (status)
  				goto out;
  			break;
  		case NFS4_OPEN_CLAIM_PREVIOUS:

  			open->op_openowner->oo_flags |= NFS4_OO_CONFIRMED;

  			status = nfs4_check_open_reclaim(&open->op_clientid);
  			if (status)
  				goto out;

  		case NFS4_OPEN_CLAIM_FH:
  		case NFS4_OPEN_CLAIM_DELEG_CUR_FH:

  			status = do_open_fhandle(rqstp, &cstate->current_fh,
  						 open);

  			if (status)
  				goto out;
  			break;

  		case NFS4_OPEN_CLAIM_DELEG_PREV_FH:

               	case NFS4_OPEN_CLAIM_DELEGATE_PREV:

  			open->op_openowner->oo_flags |= NFS4_OO_CONFIRMED;

  			dprintk("NFSD: unsupported OPEN claim type %d
  ",

  				open->op_claim_type);
  			status = nfserr_notsupp;
  			goto out;
  		default:

  			dprintk("NFSD: Invalid OPEN claim type %d
  ",

  				open->op_claim_type);
  			status = nfserr_inval;
  			goto out;
  	}
  	/*
  	 * nfsd4_process_open2() does the actual opening of the file.  If
  	 * successful, it (1) truncates the file if open->op_truncate was
  	 * set, (2) sets open->op_stateid, (3) sets open->op_delegation.
  	 */

  	status = nfsd4_process_open2(rqstp, &cstate->current_fh, open);

  	WARN_ON(status && open->op_created);

  out:

  	nfsd4_cleanup_open_state(open, status);

  	if (open->op_openowner)
  		cstate->replay_owner = &open->op_openowner->oo_owner;

  	else

  		nfs4_unlock_state();

  	return status;
  }
  
  /*
   * filehandle-manipulating ops.
   */

  static __be32

  nfsd4_getfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	    struct svc_fh **getfh)

  {

  	if (!cstate->current_fh.fh_dentry)

  		return nfserr_nofilehandle;

  	*getfh = &cstate->current_fh;

  	return nfs_ok;
  }

  static __be32

  nfsd4_putfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	    struct nfsd4_putfh *putfh)

  {

  	fh_put(&cstate->current_fh);
  	cstate->current_fh.fh_handle.fh_size = putfh->pf_fhlen;
  	memcpy(&cstate->current_fh.fh_handle.fh_base, putfh->pf_fhval,
  	       putfh->pf_fhlen);

  	return fh_verify(rqstp, &cstate->current_fh, 0, NFSD_MAY_BYPASS_GSS);

  }

  static __be32

  nfsd4_putrootfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  		void *arg)

  {

  	__be32 status;

  	fh_put(&cstate->current_fh);

  	status = exp_pseudoroot(rqstp, &cstate->current_fh);

  	return status;
  }

  static __be32

  nfsd4_restorefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  		void *arg)

  {

  	if (!cstate->save_fh.fh_dentry)

  		return nfserr_restorefh;

  	fh_dup2(&cstate->current_fh, &cstate->save_fh);

  	return nfs_ok;
  }

  static __be32

  nfsd4_savefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     void *arg)

  {

  	if (!cstate->current_fh.fh_dentry)

  		return nfserr_nofilehandle;

  	fh_dup2(&cstate->save_fh, &cstate->current_fh);

  	return nfs_ok;
  }
  
  /*
   * misc nfsv4 ops
   */

  static __be32

  nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_access *access)

  {
  	if (access->ac_req_access & ~NFS3_ACCESS_FULL)
  		return nfserr_inval;
  
  	access->ac_resp_access = access->ac_req_access;

  	return nfsd_access(rqstp, &cstate->current_fh, &access->ac_resp_access,
  			   &access->ac_supported);

  }

  static __be32

  nfsd4_commit(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_commit *commit)

  {

  	u32 *p = (u32 *)commit->co_verf.data;
  	*p++ = nfssvc_boot.tv_sec;
  	*p++ = nfssvc_boot.tv_usec;

  	return nfsd_commit(rqstp, &cstate->current_fh, commit->co_offset,

  			     commit->co_count);

  }

  static __be32

  nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_create *create)

  {
  	struct svc_fh resfh;

  	__be32 status;

  	dev_t rdev;
  
  	fh_init(&resfh, NFS4_FHSIZE);

  	status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR,
  			   NFSD_MAY_CREATE);

  	if (status)
  		return status;

  	status = check_attr_support(rqstp, cstate, create->cr_bmval,
  				    nfsd_attrmask);
  	if (status)
  		return status;

  	switch (create->cr_type) {
  	case NF4LNK:
  		/* ugh! we have to null-terminate the linktext, or
  		 * vfs_symlink() will choke.  it is always safe to
  		 * null-terminate by brute force, since at worst we
  		 * will overwrite the first byte of the create namelen
  		 * in the XDR buffer, which has already been extracted
  		 * during XDR decode.
  		 */
  		create->cr_linkname[create->cr_linklen] = 0;

  		status = nfsd_symlink(rqstp, &cstate->current_fh,
  				      create->cr_name, create->cr_namelen,
  				      create->cr_linkname, create->cr_linklen,
  				      &resfh, &create->cr_iattr);

  		break;
  
  	case NF4BLK:
  		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
  		if (MAJOR(rdev) != create->cr_specdata1 ||
  		    MINOR(rdev) != create->cr_specdata2)
  			return nfserr_inval;

  		status = nfsd_create(rqstp, &cstate->current_fh,
  				     create->cr_name, create->cr_namelen,
  				     &create->cr_iattr, S_IFBLK, rdev, &resfh);

  		break;
  
  	case NF4CHR:
  		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
  		if (MAJOR(rdev) != create->cr_specdata1 ||
  		    MINOR(rdev) != create->cr_specdata2)
  			return nfserr_inval;

  		status = nfsd_create(rqstp, &cstate->current_fh,
  				     create->cr_name, create->cr_namelen,
  				     &create->cr_iattr,S_IFCHR, rdev, &resfh);

  		break;
  
  	case NF4SOCK:

  		status = nfsd_create(rqstp, &cstate->current_fh,
  				     create->cr_name, create->cr_namelen,
  				     &create->cr_iattr, S_IFSOCK, 0, &resfh);

  		break;
  
  	case NF4FIFO:

  		status = nfsd_create(rqstp, &cstate->current_fh,
  				     create->cr_name, create->cr_namelen,
  				     &create->cr_iattr, S_IFIFO, 0, &resfh);

  		break;
  
  	case NF4DIR:
  		create->cr_iattr.ia_valid &= ~ATTR_SIZE;

  		status = nfsd_create(rqstp, &cstate->current_fh,
  				     create->cr_name, create->cr_namelen,
  				     &create->cr_iattr, S_IFDIR, 0, &resfh);

  		break;
  
  	default:
  		status = nfserr_badtype;
  	}

  	if (status)
  		goto out;

  	if (create->cr_acl != NULL)
  		do_set_nfs4_acl(rqstp, &resfh, create->cr_acl,
  				create->cr_bmval);
  
  	fh_unlock(&cstate->current_fh);
  	set_change_info(&create->cr_cinfo, &cstate->current_fh);
  	fh_dup2(&cstate->current_fh, &resfh);
  out:

  	fh_put(&resfh);
  	return status;
  }

  static __be32

  nfsd4_getattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_getattr *getattr)

  {

  	__be32 status;

  	status = fh_verify(rqstp, &cstate->current_fh, 0, NFSD_MAY_NOP);

  	if (status)
  		return status;
  
  	if (getattr->ga_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
  		return nfserr_inval;

  	getattr->ga_bmval[0] &= nfsd_suppattrs0(cstate->minorversion);
  	getattr->ga_bmval[1] &= nfsd_suppattrs1(cstate->minorversion);
  	getattr->ga_bmval[2] &= nfsd_suppattrs2(cstate->minorversion);

  	getattr->ga_fhp = &cstate->current_fh;

  	return nfs_ok;
  }

  static __be32

  nfsd4_link(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	   struct nfsd4_link *link)

  {

  	__be32 status = nfserr_nofilehandle;

  	if (!cstate->save_fh.fh_dentry)

  		return status;

  	status = nfsd_link(rqstp, &cstate->current_fh,
  			   link->li_name, link->li_namelen, &cstate->save_fh);

  	if (!status)

  		set_change_info(&link->li_cinfo, &cstate->current_fh);

  	return status;
  }

  static __be32 nfsd4_do_lookupp(struct svc_rqst *rqstp, struct svc_fh *fh)

  {
  	struct svc_fh tmp_fh;

  	__be32 ret;

  
  	fh_init(&tmp_fh, NFS4_FHSIZE);

  	ret = exp_pseudoroot(rqstp, &tmp_fh);
  	if (ret)

  		return ret;

  	if (tmp_fh.fh_dentry == fh->fh_dentry) {

  		fh_put(&tmp_fh);
  		return nfserr_noent;
  	}
  	fh_put(&tmp_fh);

  	return nfsd_lookup(rqstp, fh, "..", 2, fh);
  }
  
  static __be32
  nfsd4_lookupp(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      void *arg)
  {
  	return nfsd4_do_lookupp(rqstp, &cstate->current_fh);

  }

  static __be32

  nfsd4_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_lookup *lookup)

  {

  	return nfsd_lookup(rqstp, &cstate->current_fh,
  			   lookup->lo_name, lookup->lo_len,
  			   &cstate->current_fh);

  }

  static __be32

  nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	   struct nfsd4_read *read)

  {

  	__be32 status;

  
  	/* no need to check permission - this will be done in nfsd_read() */

  	read->rd_filp = NULL;

  	if (read->rd_offset >= OFFSET_MAX)
  		return nfserr_inval;
  
  	nfs4_lock_state();
  	/* check stateid */

  	if ((status = nfs4_preprocess_stateid_op(cstate, &read->rd_stateid,
  						 RD_STATE, &read->rd_filp))) {

  		dprintk("NFSD: nfsd4_read: couldn't process stateid!
  ");
  		goto out;
  	}

  	if (read->rd_filp)
  		get_file(read->rd_filp);

  	status = nfs_ok;
  out:
  	nfs4_unlock_state();
  	read->rd_rqstp = rqstp;

  	read->rd_fhp = &cstate->current_fh;

  	return status;
  }

  static __be32

  nfsd4_readdir(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_readdir *readdir)

  {
  	u64 cookie = readdir->rd_cookie;
  	static const nfs4_verifier zeroverf;
  
  	/* no need to check permission - this will be done in nfsd_readdir() */
  
  	if (readdir->rd_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
  		return nfserr_inval;

  	readdir->rd_bmval[0] &= nfsd_suppattrs0(cstate->minorversion);
  	readdir->rd_bmval[1] &= nfsd_suppattrs1(cstate->minorversion);
  	readdir->rd_bmval[2] &= nfsd_suppattrs2(cstate->minorversion);

  	if ((cookie == 1) || (cookie == 2) ||

  	    (cookie == 0 && memcmp(readdir->rd_verf.data, zeroverf.data, NFS4_VERIFIER_SIZE)))
  		return nfserr_bad_cookie;
  
  	readdir->rd_rqstp = rqstp;

  	readdir->rd_fhp = &cstate->current_fh;

  	return nfs_ok;
  }

  static __be32

  nfsd4_readlink(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	       struct nfsd4_readlink *readlink)

  {
  	readlink->rl_rqstp = rqstp;

  	readlink->rl_fhp = &cstate->current_fh;

  	return nfs_ok;
  }

  static __be32

  nfsd4_remove(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_remove *remove)

  {

  	__be32 status;

  	if (locks_in_grace())

  		return nfserr_grace;

  	status = nfsd_unlink(rqstp, &cstate->current_fh, 0,
  			     remove->rm_name, remove->rm_namelen);

  	if (!status) {

  		fh_unlock(&cstate->current_fh);
  		set_change_info(&remove->rm_cinfo, &cstate->current_fh);

  	}
  	return status;
  }

  static __be32

  nfsd4_rename(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_rename *rename)

  {

  	__be32 status = nfserr_nofilehandle;

  	if (!cstate->save_fh.fh_dentry)

  		return status;

  	if (locks_in_grace() && !(cstate->save_fh.fh_export->ex_flags

  					& NFSEXP_NOSUBTREECHECK))
  		return nfserr_grace;

  	status = nfsd_rename(rqstp, &cstate->save_fh, rename->rn_sname,
  			     rename->rn_snamelen, &cstate->current_fh,

  			     rename->rn_tname, rename->rn_tnamelen);
  
  	/* the underlying filesystem returns different error's than required
  	 * by NFSv4. both save_fh and current_fh have been verified.. */
  	if (status == nfserr_isdir)
  		status = nfserr_exist;
  	else if ((status == nfserr_notdir) &&

                    (S_ISDIR(cstate->save_fh.fh_dentry->d_inode->i_mode) &&
                     S_ISDIR(cstate->current_fh.fh_dentry->d_inode->i_mode)))

  		status = nfserr_exist;

  
  	if (!status) {

  		set_change_info(&rename->rn_sinfo, &cstate->current_fh);
  		set_change_info(&rename->rn_tinfo, &cstate->save_fh);

  	}
  	return status;
  }

  static __be32

  nfsd4_secinfo(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_secinfo *secinfo)
  {
  	struct svc_fh resfh;
  	struct svc_export *exp;
  	struct dentry *dentry;
  	__be32 err;
  
  	fh_init(&resfh, NFS4_FHSIZE);

  	err = fh_verify(rqstp, &cstate->current_fh, S_IFDIR, NFSD_MAY_EXEC);
  	if (err)
  		return err;

  	err = nfsd_lookup_dentry(rqstp, &cstate->current_fh,
  				    secinfo->si_name, secinfo->si_namelen,
  				    &exp, &dentry);
  	if (err)
  		return err;
  	if (dentry->d_inode == NULL) {
  		exp_put(exp);
  		err = nfserr_noent;
  	} else
  		secinfo->si_exp = exp;
  	dput(dentry);

  	if (cstate->minorversion)
  		/* See rfc 5661 section 2.6.3.1.1.8 */
  		fh_put(&cstate->current_fh);

  	return err;
  }
  
  static __be32

  nfsd4_secinfo_no_name(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_secinfo_no_name *sin)
  {
  	__be32 err;
  
  	switch (sin->sin_style) {
  	case NFS4_SECINFO_STYLE4_CURRENT_FH:
  		break;
  	case NFS4_SECINFO_STYLE4_PARENT:
  		err = nfsd4_do_lookupp(rqstp, &cstate->current_fh);
  		if (err)
  			return err;
  		break;
  	default:
  		return nfserr_inval;
  	}
  	exp_get(cstate->current_fh.fh_export);
  	sin->sin_exp = cstate->current_fh.fh_export;
  	fh_put(&cstate->current_fh);
  	return nfs_ok;
  }
  
  static __be32

  nfsd4_setattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_setattr *setattr)

  {

  	__be32 status = nfs_ok;

  	if (setattr->sa_iattr.ia_valid & ATTR_SIZE) {
  		nfs4_lock_state();

  		status = nfs4_preprocess_stateid_op(cstate,

  			&setattr->sa_stateid, WR_STATE, NULL);

  		nfs4_unlock_state();

  		if (status) {

  			dprintk("NFSD: nfsd4_setattr: couldn't process stateid!
  ");

  			return status;
  		}

  	}

  	status = fh_want_write(&cstate->current_fh);

  	if (status)
  		return status;

  	status = nfs_ok;

  
  	status = check_attr_support(rqstp, cstate, setattr->sa_bmval,
  				    nfsd_attrmask);
  	if (status)
  		goto out;

  	if (setattr->sa_acl != NULL)

  		status = nfsd4_set_nfs4_acl(rqstp, &cstate->current_fh,
  					    setattr->sa_acl);

  	if (status)

  		goto out;

  	status = nfsd_setattr(rqstp, &cstate->current_fh, &setattr->sa_iattr,

  				0, (time_t)0);

  out:

  	fh_drop_write(&cstate->current_fh);

  	return status;
  }

  static __be32

  nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	    struct nfsd4_write *write)

  {
  	stateid_t *stateid = &write->wr_stateid;
  	struct file *filp = NULL;
  	u32 *p;

  	__be32 status = nfs_ok;

  	unsigned long cnt;

  
  	/* no need to check permission - this will be done in nfsd_write() */
  
  	if (write->wr_offset >= OFFSET_MAX)
  		return nfserr_inval;
  
  	nfs4_lock_state();

  	status = nfs4_preprocess_stateid_op(cstate, stateid, WR_STATE, &filp);

  	if (filp)
  		get_file(filp);

  	nfs4_unlock_state();

  	if (status) {
  		dprintk("NFSD: nfsd4_write: couldn't process stateid!
  ");
  		return status;
  	}

  	cnt = write->wr_buflen;

  	write->wr_how_written = write->wr_stable_how;
  	p = (u32 *)write->wr_verifier.data;
  	*p++ = nfssvc_boot.tv_sec;
  	*p++ = nfssvc_boot.tv_usec;

  	status =  nfsd_write(rqstp, &cstate->current_fh, filp,
  			     write->wr_offset, rqstp->rq_vec, write->wr_vlen,

  			     &cnt, &write->wr_how_written);

  	if (filp)
  		fput(filp);

  	write->wr_bytes_written = cnt;

  	return status;

  }
  
  /* This routine never returns NFS_OK!  If there are no other errors, it
   * will return NFSERR_SAME or NFSERR_NOT_SAME depending on whether the
   * attributes matched.  VERIFY is implemented by mapping NFSERR_SAME
   * to NFS_OK after the call; NVERIFY by mapping NFSERR_NOT_SAME to NFS_OK.
   */

  static __be32

  _nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,

  	     struct nfsd4_verify *verify)

  {

  	__be32 *buf, *p;

  	int count;

  	__be32 status;

  	status = fh_verify(rqstp, &cstate->current_fh, 0, NFSD_MAY_NOP);

  	if (status)
  		return status;

  	status = check_attr_support(rqstp, cstate, verify->ve_bmval, NULL);
  	if (status)
  		return status;

  	if ((verify->ve_bmval[0] & FATTR4_WORD0_RDATTR_ERROR)
  	    || (verify->ve_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1))
  		return nfserr_inval;
  	if (verify->ve_attrlen & 3)
  		return nfserr_inval;
  
  	/* count in words:
  	 *   bitmap_len(1) + bitmap(2) + attr_len(1) = 4
  	 */
  	count = 4 + (verify->ve_attrlen >> 2);
  	buf = kmalloc(count << 2, GFP_KERNEL);
  	if (!buf)

  		return nfserr_jukebox;

  	status = nfsd4_encode_fattr(&cstate->current_fh,
  				    cstate->current_fh.fh_export,
  				    cstate->current_fh.fh_dentry, buf,

  				    &count, verify->ve_bmval,

  				    rqstp, 0);

  
  	/* this means that nfsd4_encode_fattr() ran out of space */
  	if (status == nfserr_resource && count == 0)
  		status = nfserr_not_same;
  	if (status)
  		goto out_kfree;

  	/* skip bitmap */
  	p = buf + 1 + ntohl(buf[0]);

  	status = nfserr_not_same;
  	if (ntohl(*p++) != verify->ve_attrlen)
  		goto out_kfree;
  	if (!memcmp(p, verify->ve_attrval, verify->ve_attrlen))
  		status = nfserr_same;
  
  out_kfree:
  	kfree(buf);
  	return status;
  }

  static __be32
  nfsd4_nverify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	      struct nfsd4_verify *verify)
  {
  	__be32 status;
  
  	status = _nfsd4_verify(rqstp, cstate, verify);
  	return status == nfserr_not_same ? nfs_ok : status;
  }
  
  static __be32
  nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
  	     struct nfsd4_verify *verify)
  {
  	__be32 status;
  
  	status = _nfsd4_verify(rqstp, cstate, verify);
  	return status == nfserr_same ? nfs_ok : status;
  }

  /*
   * NULL call.
   */

  static __be32

  nfsd4_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  {
  	return nfs_ok;
  }

  static inline void nfsd4_increment_op_stats(u32 opnum)
  {
  	if (opnum >= FIRST_NFS4_OP && opnum <= LAST_NFS4_OP)
  		nfsdstats.nfs4_opcount[opnum]++;
  }

  typedef __be32(*nfsd4op_func)(struct svc_rqst *, struct nfsd4_compound_state *,
  			      void *);

  typedef u32(*nfsd4op_rsize)(struct svc_rqst *, struct nfsd4_op *op);

  enum nfsd4_op_flags {
  	ALLOWED_WITHOUT_FH = 1 << 0,	/* No current filehandle required */

  	ALLOWED_ON_ABSENT_FS = 1 << 1,	/* ops processed on absent fs */
  	ALLOWED_AS_FIRST_OP = 1 << 2,	/* ops reqired first in compound */

  	/* For rfc 5661 section 2.6.3.1.1: */
  	OP_HANDLES_WRONGSEC = 1 << 3,
  	OP_IS_PUTFH_LIKE = 1 << 4,

  	/*

  	 * These are the ops whose result size we estimate before
  	 * encoding, to avoid performing an op then not being able to
  	 * respond or cache a response.  This includes writes and setattrs
  	 * as well as the operations usually called "nonidempotent":
  	 */
  	OP_MODIFIES_SOMETHING = 1 << 5,
  	/*
  	 * Cache compounds containing these ops in the xid-based drc:

  	 * We use the DRC for compounds containing non-idempotent
  	 * operations, *except* those that are 4.1-specific (since
  	 * sessions provide their own EOS), and except for stateful
  	 * operations other than setclientid and setclientid_confirm
  	 * (since sequence numbers provide EOS for open, lock, etc in
  	 * the v4.0 case).
  	 */

  	OP_CACHEME = 1 << 6,
  };
  
  struct nfsd4_operation {
  	nfsd4op_func op_func;
  	u32 op_flags;
  	char *op_name;

  	/* Try to get response size before operation */
  	nfsd4op_rsize op_rsize_bop;

  };
  
  static struct nfsd4_operation nfsd4_ops[];

  static const char *nfsd4_op_name(unsigned opnum);

  /*

   * Enforce NFSv4.1 COMPOUND ordering rules:

   *

   * Also note, enforced elsewhere:
   *	- SEQUENCE other than as first op results in
   *	  NFS4ERR_SEQUENCE_POS. (Enforced in nfsd4_sequence().)

   *	- BIND_CONN_TO_SESSION must be the only op in its compound.
   *	  (Enforced in nfsd4_bind_conn_to_session().)

   *	- DESTROY_SESSION must be the final operation in a compound, if
   *	  sessionid's in SEQUENCE and DESTROY_SESSION are the same.
   *	  (Enforced in nfsd4_destroy_session().)

   */

  static __be32 nfs41_check_op_ordering(struct nfsd4_compoundargs *args)

  {

  	struct nfsd4_op *op = &args->ops[0];
  
  	/* These ordering requirements don't apply to NFSv4.0: */
  	if (args->minorversion == 0)
  		return nfs_ok;
  	/* This is weird, but OK, not our problem: */
  	if (args->opcnt == 0)
  		return nfs_ok;
  	if (op->status == nfserr_op_illegal)
  		return nfs_ok;
  	if (!(nfsd4_ops[op->opnum].op_flags & ALLOWED_AS_FIRST_OP))
  		return nfserr_op_not_in_session;
  	if (op->opnum == OP_SEQUENCE)
  		return nfs_ok;
  	if (args->opcnt != 1)
  		return nfserr_not_only_op;
  	return nfs_ok;

  }

  static inline struct nfsd4_operation *OPDESC(struct nfsd4_op *op)
  {
  	return &nfsd4_ops[op->opnum];
  }

  bool nfsd4_cache_this_op(struct nfsd4_op *op)
  {

  	return OPDESC(op)->op_flags & OP_CACHEME;

  }

  static bool need_wrongsec_check(struct svc_rqst *rqstp)
  {
  	struct nfsd4_compoundres *resp = rqstp->rq_resp;
  	struct nfsd4_compoundargs *argp = rqstp->rq_argp;
  	struct nfsd4_op *this = &argp->ops[resp->opcnt - 1];
  	struct nfsd4_op *next = &argp->ops[resp->opcnt];
  	struct nfsd4_operation *thisd;
  	struct nfsd4_operation *nextd;
  
  	thisd = OPDESC(this);
  	/*
  	 * Most ops check wronsec on our own; only the putfh-like ops
  	 * have special rules.
  	 */
  	if (!(thisd->op_flags & OP_IS_PUTFH_LIKE))
  		return false;
  	/*
  	 * rfc 5661 2.6.3.1.1.6: don't bother erroring out a
  	 * put-filehandle operation if we're not going to use the
  	 * result:
  	 */
  	if (argp->opcnt == resp->opcnt)
  		return false;
  
  	nextd = OPDESC(next);
  	/*
  	 * Rest of 2.6.3.1.1: certain operations will return WRONGSEC
  	 * errors themselves as necessary; others should check for them
  	 * now:
  	 */
  	return !(nextd->op_flags & OP_HANDLES_WRONGSEC);
  }

  /*

   * COMPOUND call.
   */

  static __be32

  nfsd4_proc_compound(struct svc_rqst *rqstp,
  		    struct nfsd4_compoundargs *args,
  		    struct nfsd4_compoundres *resp)
  {
  	struct nfsd4_op	*op;

  	struct nfsd4_operation *opdesc;

  	struct nfsd4_compound_state *cstate = &resp->cstate;

  	int		slack_bytes;

  	u32		plen = 0;

  	__be32		status;

  	resp->xbuf = &rqstp->rq_res;

  	resp->p = rqstp->rq_res.head[0].iov_base +
  						rqstp->rq_res.head[0].iov_len;

  	resp->tagp = resp->p;
  	/* reserve space for: taglen, tag, and opcnt */
  	resp->p += 2 + XDR_QUADLEN(args->taglen);
  	resp->end = rqstp->rq_res.head[0].iov_base + PAGE_SIZE;
  	resp->taglen = args->taglen;
  	resp->tag = args->tag;
  	resp->opcnt = 0;
  	resp->rqstp = rqstp;

  	resp->cstate.minorversion = args->minorversion;

  	resp->cstate.replay_owner = NULL;

  	resp->cstate.session = NULL;

  	fh_init(&resp->cstate.current_fh, NFS4_FHSIZE);
  	fh_init(&resp->cstate.save_fh, NFS4_FHSIZE);

  	/*
  	 * Don't use the deferral mechanism for NFSv4; compounds make it
  	 * too hard to avoid non-idempotency problems.
  	 */
  	rqstp->rq_usedeferral = 0;

  
  	/*
  	 * According to RFC3010, this takes precedence over all other errors.
  	 */
  	status = nfserr_minor_vers_mismatch;

  	if (args->minorversion > nfsd_supported_minorversion)

  		goto out;

  	status = nfs41_check_op_ordering(args);
  	if (status) {

  		op = &args->ops[0];

  		op->status = status;

  		goto encode_op;
  	}

  	while (!status && resp->opcnt < args->opcnt) {
  		op = &args->ops[resp->opcnt++];

  		dprintk("nfsv4 compound op #%d/%d: %d (%s)
  ",
  			resp->opcnt, args->opcnt, op->opnum,
  			nfsd4_op_name(op->opnum));

  		/*
  		 * The XDR decode routines may have pre-set op->status;
  		 * for example, if there is a miscellaneous XDR error
  		 * it will be set to nfserr_bad_xdr.
  		 */
  		if (op->status)
  			goto encode_op;
  
  		/* We must be able to encode a successful response to
  		 * this operation, with enough room left over to encode a
  		 * failed response to the next operation.  If we don't
  		 * have enough room, fail with ERR_RESOURCE.
  		 */

  		slack_bytes = (char *)resp->end - (char *)resp->p;
  		if (slack_bytes < COMPOUND_SLACK_SPACE
  				+ COMPOUND_ERR_SLACK_SPACE) {
  			BUG_ON(slack_bytes < COMPOUND_ERR_SLACK_SPACE);

  			op->status = nfserr_resource;
  			goto encode_op;
  		}

  		opdesc = OPDESC(op);

  		if (!cstate->current_fh.fh_dentry) {

  			if (!(opdesc->op_flags & ALLOWED_WITHOUT_FH)) {

  				op->status = nfserr_nofilehandle;
  				goto encode_op;
  			}

  		} else if (cstate->current_fh.fh_export->ex_fslocs.migrated &&
  			  !(opdesc->op_flags & ALLOWED_ON_ABSENT_FS)) {

  			op->status = nfserr_moved;

  			goto encode_op;
  		}

  		/* If op is non-idempotent */
  		if (opdesc->op_flags & OP_MODIFIES_SOMETHING) {
  			plen = opdesc->op_rsize_bop(rqstp, op);
  			op->status = nfsd4_check_resp_size(resp, plen);
  		}
  
  		if (op->status)
  			goto encode_op;

  		if (opdesc->op_func)
  			op->status = opdesc->op_func(rqstp, cstate, &op->u);
  		else

  			BUG_ON(op->status == nfs_ok);

  		if (!op->status && need_wrongsec_check(rqstp))
  			op->status = check_nfsd_access(cstate->current_fh.fh_export, rqstp);

  encode_op:

  		/* Only from SEQUENCE */

  		if (resp->cstate.status == nfserr_replay_cache) {
  			dprintk("%s NFS4.1 replay from cache
  ", __func__);

  			status = op->status;

  			goto out;
  		}

  		if (op->status == nfserr_replay_me) {

  			op->replay = &cstate->replay_owner->so_replay;

  			nfsd4_encode_replay(resp, op);
  			status = op->status = op->replay->rp_status;
  		} else {
  			nfsd4_encode_operation(resp, op);
  			status = op->status;
  		}

  
  		dprintk("nfsv4 compound op %p opcnt %d #%d: %d: status %d
  ",
  			args->ops, args->opcnt, resp->opcnt, op->opnum,
  			be32_to_cpu(status));

  		if (cstate->replay_owner) {

  			nfs4_unlock_state();

  			cstate->replay_owner = NULL;

  		}

  		/* XXX Ugh, we need to get rid of this kind of special case: */
  		if (op->opnum == OP_READ && op->u.read.rd_filp)
  			fput(op->u.read.rd_filp);

  
  		nfsd4_increment_op_stats(op->opnum);

  	}

  	resp->cstate.status = status;

  	fh_put(&resp->cstate.current_fh);
  	fh_put(&resp->cstate.save_fh);
  	BUG_ON(resp->cstate.replay_owner);

  out:

  	/* Reset deferral mechanism for RPC deferrals */
  	rqstp->rq_usedeferral = 1;

  	dprintk("nfsv4 compound returned %d
  ", ntohl(status));

  	return status;
  }

  #define op_encode_hdr_size		(2)
  #define op_encode_stateid_maxsz		(XDR_QUADLEN(NFS4_STATEID_SIZE))
  #define op_encode_verifier_maxsz	(XDR_QUADLEN(NFS4_VERIFIER_SIZE))
  #define op_encode_change_info_maxsz	(5)
  #define nfs4_fattr_bitmap_maxsz		(4)
  
  #define op_encode_lockowner_maxsz	(1 + XDR_QUADLEN(IDMAP_NAMESZ))
  #define op_encode_lock_denied_maxsz	(8 + op_encode_lockowner_maxsz)
  
  #define nfs4_owner_maxsz		(1 + XDR_QUADLEN(IDMAP_NAMESZ))
  
  #define op_encode_ace_maxsz		(3 + nfs4_owner_maxsz)
  #define op_encode_delegation_maxsz	(1 + op_encode_stateid_maxsz + 1 + \
  					 op_encode_ace_maxsz)
  
  #define op_encode_channel_attrs_maxsz	(6 + 1 + 1)
  
  static inline u32 nfsd4_only_status_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_status_stateid_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_stateid_maxsz)* sizeof(__be32);
  }
  
  static inline u32 nfsd4_commit_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_verifier_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_create_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_change_info_maxsz
  		+ nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_link_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_change_info_maxsz)
  		* sizeof(__be32);
  }
  
  static inline u32 nfsd4_lock_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_lock_denied_maxsz)
  		* sizeof(__be32);
  }
  
  static inline u32 nfsd4_open_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_stateid_maxsz
  		+ op_encode_change_info_maxsz + 1
  		+ nfs4_fattr_bitmap_maxsz
  		+ op_encode_delegation_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_read_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	u32 maxcount = 0, rlen = 0;
  
  	maxcount = svc_max_payload(rqstp);
  	rlen = op->u.read.rd_length;
  
  	if (rlen > maxcount)
  		rlen = maxcount;
  
  	return (op_encode_hdr_size + 2) * sizeof(__be32) + rlen;
  }
  
  static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	u32 rlen = op->u.readdir.rd_maxcount;
  
  	if (rlen > PAGE_SIZE)
  		rlen = PAGE_SIZE;
  
  	return (op_encode_hdr_size + op_encode_verifier_maxsz)
  		 * sizeof(__be32) + rlen;
  }
  
  static inline u32 nfsd4_remove_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_change_info_maxsz)
  		* sizeof(__be32);
  }
  
  static inline u32 nfsd4_rename_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_change_info_maxsz
  		+ op_encode_change_info_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_setattr_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_setclientid_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + 2 + 1024) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_write_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + op_encode_verifier_maxsz) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_exchange_id_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + 2 + 1 + /* eir_clientid, eir_sequenceid */\
  		1 + 1 + 0 + /* eir_flags, spr_how, SP4_NONE (for now) */\
  		2 + /*eir_server_owner.so_minor_id */\
  		/* eir_server_owner.so_major_id<> */\
  		XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 +\
  		/* eir_server_scope<> */\
  		XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 +\
  		1 + /* eir_server_impl_id array length */\
  		0 /* ignored eir_server_impl_id contents */) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_bind_conn_to_session_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + \
  		XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN) + /* bctsr_sessid */\
  		2 /* bctsr_dir, use_conn_in_rdma_mode */) * sizeof(__be32);
  }
  
  static inline u32 nfsd4_create_session_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
  {
  	return (op_encode_hdr_size + \
  		XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN) + /* sessionid */\
  		2 + /* csr_sequence, csr_flags */\
  		op_encode_channel_attrs_maxsz + \
  		op_encode_channel_attrs_maxsz) * sizeof(__be32);
  }

  static struct nfsd4_operation nfsd4_ops[] = {

  	[OP_ACCESS] = {
  		.op_func = (nfsd4op_func)nfsd4_access,

  		.op_name = "OP_ACCESS",

  	},
  	[OP_CLOSE] = {
  		.op_func = (nfsd4op_func)nfsd4_close,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_CLOSE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,

  	},
  	[OP_COMMIT] = {
  		.op_func = (nfsd4op_func)nfsd4_commit,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_COMMIT",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_commit_rsize,

  	},
  	[OP_CREATE] = {
  		.op_func = (nfsd4op_func)nfsd4_create,

  		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_CREATE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_create_rsize,

  	},
  	[OP_DELEGRETURN] = {
  		.op_func = (nfsd4op_func)nfsd4_delegreturn,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_DELEGRETURN",

  		.op_rsize_bop = nfsd4_only_status_rsize,

  	},
  	[OP_GETATTR] = {
  		.op_func = (nfsd4op_func)nfsd4_getattr,

  		.op_flags = ALLOWED_ON_ABSENT_FS,

  		.op_name = "OP_GETATTR",

  	},
  	[OP_GETFH] = {
  		.op_func = (nfsd4op_func)nfsd4_getfh,

  		.op_name = "OP_GETFH",

  	},
  	[OP_LINK] = {
  		.op_func = (nfsd4op_func)nfsd4_link,

  		.op_flags = ALLOWED_ON_ABSENT_FS | OP_MODIFIES_SOMETHING
  				| OP_CACHEME,

  		.op_name = "OP_LINK",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_link_rsize,

  	},
  	[OP_LOCK] = {
  		.op_func = (nfsd4op_func)nfsd4_lock,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_LOCK",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_lock_rsize,

  	},
  	[OP_LOCKT] = {
  		.op_func = (nfsd4op_func)nfsd4_lockt,

  		.op_name = "OP_LOCKT",

  	},
  	[OP_LOCKU] = {
  		.op_func = (nfsd4op_func)nfsd4_locku,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_LOCKU",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,

  	},
  	[OP_LOOKUP] = {
  		.op_func = (nfsd4op_func)nfsd4_lookup,

  		.op_flags = OP_HANDLES_WRONGSEC,

  		.op_name = "OP_LOOKUP",

  	},
  	[OP_LOOKUPP] = {
  		.op_func = (nfsd4op_func)nfsd4_lookupp,

  		.op_flags = OP_HANDLES_WRONGSEC,

  		.op_name = "OP_LOOKUPP",

  	},
  	[OP_NVERIFY] = {
  		.op_func = (nfsd4op_func)nfsd4_nverify,

  		.op_name = "OP_NVERIFY",

  	},
  	[OP_OPEN] = {
  		.op_func = (nfsd4op_func)nfsd4_open,

  		.op_flags = OP_HANDLES_WRONGSEC | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_OPEN",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_open_rsize,

  	},
  	[OP_OPEN_CONFIRM] = {
  		.op_func = (nfsd4op_func)nfsd4_open_confirm,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_OPEN_CONFIRM",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,

  	},
  	[OP_OPEN_DOWNGRADE] = {
  		.op_func = (nfsd4op_func)nfsd4_open_downgrade,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_OPEN_DOWNGRADE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,

  	},
  	[OP_PUTFH] = {
  		.op_func = (nfsd4op_func)nfsd4_putfh,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_PUTFH",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  	[OP_PUTPUBFH] = {

  		.op_func = (nfsd4op_func)nfsd4_putrootfh,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_PUTPUBFH",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  	[OP_PUTROOTFH] = {
  		.op_func = (nfsd4op_func)nfsd4_putrootfh,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_PUTROOTFH",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},
  	[OP_READ] = {
  		.op_func = (nfsd4op_func)nfsd4_read,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_READ",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_read_rsize,

  	},
  	[OP_READDIR] = {
  		.op_func = (nfsd4op_func)nfsd4_readdir,

  		.op_flags = OP_MODIFIES_SOMETHING,

  		.op_name = "OP_READDIR",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_readdir_rsize,

  	},
  	[OP_READLINK] = {
  		.op_func = (nfsd4op_func)nfsd4_readlink,

  		.op_name = "OP_READLINK",

  	},
  	[OP_REMOVE] = {
  		.op_func = (nfsd4op_func)nfsd4_remove,

  		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_REMOVE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_remove_rsize,

  	},
  	[OP_RENAME] = {
  		.op_func = (nfsd4op_func)nfsd4_rename,

  		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_RENAME",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_rename_rsize,

  	},
  	[OP_RENEW] = {
  		.op_func = (nfsd4op_func)nfsd4_renew,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_RENEW",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},
  	[OP_RESTOREFH] = {
  		.op_func = (nfsd4op_func)nfsd4_restorefh,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_RESTOREFH",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},
  	[OP_SAVEFH] = {
  		.op_func = (nfsd4op_func)nfsd4_savefh,

  		.op_flags = OP_HANDLES_WRONGSEC | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_SAVEFH",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  	[OP_SECINFO] = {
  		.op_func = (nfsd4op_func)nfsd4_secinfo,

  		.op_flags = OP_HANDLES_WRONGSEC,

  		.op_name = "OP_SECINFO",

  	},

  	[OP_SETATTR] = {
  		.op_func = (nfsd4op_func)nfsd4_setattr,

  		.op_name = "OP_SETATTR",

  		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_setattr_rsize,

  	},
  	[OP_SETCLIENTID] = {
  		.op_func = (nfsd4op_func)nfsd4_setclientid,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_SETCLIENTID",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_setclientid_rsize,

  	},
  	[OP_SETCLIENTID_CONFIRM] = {
  		.op_func = (nfsd4op_func)nfsd4_setclientid_confirm,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS

  				| OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_SETCLIENTID_CONFIRM",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},
  	[OP_VERIFY] = {
  		.op_func = (nfsd4op_func)nfsd4_verify,

  		.op_name = "OP_VERIFY",

  	},
  	[OP_WRITE] = {
  		.op_func = (nfsd4op_func)nfsd4_write,

  		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,

  		.op_name = "OP_WRITE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_write_rsize,

  	},
  	[OP_RELEASE_LOCKOWNER] = {
  		.op_func = (nfsd4op_func)nfsd4_release_lockowner,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_RELEASE_LOCKOWNER",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  
  	/* NFSv4.1 operations */
  	[OP_EXCHANGE_ID] = {
  		.op_func = (nfsd4op_func)nfsd4_exchange_id,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_EXCHANGE_ID",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_exchange_id_rsize,

  	},

  	[OP_BIND_CONN_TO_SESSION] = {
  		.op_func = (nfsd4op_func)nfsd4_bind_conn_to_session,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_BIND_CONN_TO_SESSION",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_bind_conn_to_session_rsize,

  	},

  	[OP_CREATE_SESSION] = {
  		.op_func = (nfsd4op_func)nfsd4_create_session,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_CREATE_SESSION",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_create_session_rsize,

  	},
  	[OP_DESTROY_SESSION] = {
  		.op_func = (nfsd4op_func)nfsd4_destroy_session,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_DESTROY_SESSION",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},
  	[OP_SEQUENCE] = {
  		.op_func = (nfsd4op_func)nfsd4_sequence,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,

  		.op_name = "OP_SEQUENCE",
  	},

  	[OP_DESTROY_CLIENTID] = {

  		.op_func = (nfsd4op_func)nfsd4_destroy_clientid,

  		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
  				| OP_MODIFIES_SOMETHING,

  		.op_name = "OP_DESTROY_CLIENTID",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  	[OP_RECLAIM_COMPLETE] = {
  		.op_func = (nfsd4op_func)nfsd4_reclaim_complete,

  		.op_flags = ALLOWED_WITHOUT_FH | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_RECLAIM_COMPLETE",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  	[OP_SECINFO_NO_NAME] = {
  		.op_func = (nfsd4op_func)nfsd4_secinfo_no_name,

  		.op_flags = OP_HANDLES_WRONGSEC,

  		.op_name = "OP_SECINFO_NO_NAME",
  	},

  	[OP_TEST_STATEID] = {
  		.op_func = (nfsd4op_func)nfsd4_test_stateid,
  		.op_flags = ALLOWED_WITHOUT_FH,
  		.op_name = "OP_TEST_STATEID",
  	},

  	[OP_FREE_STATEID] = {
  		.op_func = (nfsd4op_func)nfsd4_free_stateid,

  		.op_flags = ALLOWED_WITHOUT_FH | OP_MODIFIES_SOMETHING,

  		.op_name = "OP_FREE_STATEID",

  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,

  	},

  };

  static const char *nfsd4_op_name(unsigned opnum)

  {
  	if (opnum < ARRAY_SIZE(nfsd4_ops))
  		return nfsd4_ops[opnum].op_name;
  	return "unknown_operation";
  }

  #define nfsd4_voidres			nfsd4_voidargs

  struct nfsd4_voidargs { int dummy; };

  static struct svc_procedure		nfsd_procedures4[2] = {

  	[NFSPROC4_NULL] = {
  		.pc_func = (svc_procfunc) nfsd4_proc_null,
  		.pc_encode = (kxdrproc_t) nfs4svc_encode_voidres,
  		.pc_argsize = sizeof(struct nfsd4_voidargs),
  		.pc_ressize = sizeof(struct nfsd4_voidres),
  		.pc_cachetype = RC_NOCACHE,
  		.pc_xdrressize = 1,
  	},
  	[NFSPROC4_COMPOUND] = {
  		.pc_func = (svc_procfunc) nfsd4_proc_compound,
  		.pc_decode = (kxdrproc_t) nfs4svc_decode_compoundargs,
  		.pc_encode = (kxdrproc_t) nfs4svc_encode_compoundres,
  		.pc_argsize = sizeof(struct nfsd4_compoundargs),
  		.pc_ressize = sizeof(struct nfsd4_compoundres),

  		.pc_release = nfsd4_release_compoundargs,

  		.pc_cachetype = RC_NOCACHE,
  		.pc_xdrressize = NFSD_BUFSIZE/4,
  	},

  };
  
  struct svc_version	nfsd_version4 = {
  		.vs_vers	= 4,
  		.vs_nproc	= 2,
  		.vs_proc	= nfsd_procedures4,
  		.vs_dispatch	= nfsd_dispatch,
  		.vs_xdrsize	= NFS4_SVC_XDRSIZE,
  };
  
  /*
   * Local variables:
   *  c-basic-offset: 8
   * End:
   */