/*	$NetBSD: puffs_subr.c,v 1.66 2008/11/16 19:34:30 pooka Exp $	*/

/*
 * Copyright (c) 2006, 2007  Antti Kantee.  All Rights Reserved.
 *
 * Development of this software was supported by the
 * Ulla Tuominen Foundation and the Finnish Cultural Foundation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <sys/param.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/poll.h>
#include <sys/proc.h>

#include <vfs/puffs/puffs_msgif.h>
#include <vfs/puffs/puffs_sys.h>

MALLOC_DEFINE(M_PUFFS, "puffs", "PUFFS");

#ifdef PUFFSDEBUG
int puffsdebug = 1;
#endif

void
puffs_makecn(struct puffs_kcn *pkcn, struct puffs_kcred *pkcr,
	const struct namecache *ncp, struct ucred *cred)
{
	KKASSERT(ncp->nc_nlen < sizeof(pkcn->pkcn_name));
	pkcn->pkcn_namelen =  ncp->nc_nlen;
	strlcpy(pkcn->pkcn_name, ncp->nc_name, sizeof(pkcn->pkcn_name));

	puffs_credcvt(pkcr, cred);
}

/*
 * Convert given credentials to struct puffs_kcred for userspace.
 */
void
puffs_credcvt(struct puffs_kcred *pkcr, struct ucred *cred)
{

	memset(pkcr, 0, sizeof(struct puffs_kcred));

	if (cred == NOCRED || cred == FSCRED) {
		pkcr->pkcr_type = PUFFCRED_TYPE_INTERNAL;
		if (cred == NOCRED)
			pkcr->pkcr_internal = PUFFCRED_CRED_NOCRED;
		if (cred == FSCRED)
			pkcr->pkcr_internal = PUFFCRED_CRED_FSCRED;
	} else {
		pkcr->pkcr_type = PUFFCRED_TYPE_UUC;
		cru2x(cred, &pkcr->pkcr_uuc);
	}
}

void
puffs_parkdone_asyncbioread(struct puffs_mount *pmp,
	struct puffs_req *preq, void *arg)
{
	struct puffs_vnmsg_read *read_msg = (void *)preq;
	struct buf *bp = arg;
	size_t moved;

	DPRINTF(("%s\n", __func__));

	bp->b_error = checkerr(pmp, preq->preq_rv, __func__);
	if (bp->b_error == 0) {
		if (read_msg->pvnr_resid > bp->b_bcount) {
			puffs_senderr(pmp, PUFFS_ERR_READ, E2BIG,
			    "resid grew", preq->preq_cookie);
			bp->b_error = E2BIG;
		} else {
			moved = bp->b_bcount - read_msg->pvnr_resid;
			bp->b_resid = read_msg->pvnr_resid;

			memcpy(bp->b_data, read_msg->pvnr_data, moved);
		}
	}

	bpdone(bp, 0);
}

void
puffs_parkdone_asyncbiowrite(struct puffs_mount *pmp,
	struct puffs_req *preq, void *arg)
{
	struct puffs_vnmsg_write *write_msg = (void *)preq;
	struct buf *bp = arg;

	DPRINTF(("%s\n", __func__));

	bp->b_error = checkerr(pmp, preq->preq_rv, __func__);
	if (bp->b_error == 0) {
		if (write_msg->pvnr_resid > bp->b_bcount) {
			puffs_senderr(pmp, PUFFS_ERR_WRITE, E2BIG,
			    "resid grew", preq->preq_cookie);
			bp->b_error = E2BIG;
		} else {
			bp->b_resid = write_msg->pvnr_resid;
		}
	}

	bpdone(bp, 0);
}

/* XXX: userspace can leak kernel resources */
void
puffs_parkdone_poll(struct puffs_mount *pmp, struct puffs_req *preq, void *arg)
{
	struct puffs_vnmsg_poll *poll_msg = (void *)preq;
	struct puffs_node *pn = arg;
	int revents, error;

	error = checkerr(pmp, preq->preq_rv, __func__);
	if (error)
		revents = poll_msg->pvnr_events;
	else
		revents = POLLERR;

	lockmgr(&pn->pn_mtx, LK_EXCLUSIVE);
	pn->pn_revents |= revents;
	lockmgr(&pn->pn_mtx, LK_RELEASE);

#ifdef XXXDF
	selnotify(&pn->pn_sel, revents, 0);
#endif

	puffs_releasenode(pn);
}

void
puffs_mp_reference(struct puffs_mount *pmp)
{

	KKASSERT(lockstatus(&pmp->pmp_lock, curthread) == LK_EXCLUSIVE);
	pmp->pmp_refcount++;
}

void
puffs_mp_release(struct puffs_mount *pmp)
{

	KKASSERT(lockstatus(&pmp->pmp_lock, curthread) == LK_EXCLUSIVE);
	if (--pmp->pmp_refcount == 0)
		cv_broadcast(&pmp->pmp_refcount_cv);
}

void
puffs_senderr(struct puffs_mount *pmp, int type, int error,
	const char *str, puffs_cookie_t ck)
{
	struct puffs_msgpark *park;
	struct puffs_error *perr;

	puffs_msgmem_alloc(sizeof(struct puffs_error), &park, (void *)&perr, 1);
	puffs_msg_setfaf(park);
	puffs_msg_setinfo(park, PUFFSOP_ERROR, type, ck);

	perr->perr_error = error;
	strlcpy(perr->perr_str, str, sizeof(perr->perr_str));

	puffs_msg_enqueue(pmp, park);
	puffs_msgmem_release(park);
}