ufs_quota.c

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/*
 * Copyright (c) 1982, 1986, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Robert Elz at The University of Melbourne.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``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.
 *
 *	@(#)ufs_quota.c	8.2 (Berkeley) 12/30/93
 */
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/mount.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>

/*
 * Quota name to error message mapping.
 */
static char *quotatypes[] = INITQFNAMES;

/*
 * Set up the quotas for an inode.
 *
 * This routine completely defines the semantics of quotas.
 * If other criterion want to be used to establish quotas, the
 * MAXQUOTAS value in quotas.h should be increased, and the
 * additional dquots set up here.
 */
int
getinoquota(ip)
	register struct inode *ip;
{
	struct ufsmount *ump;
	struct vnode *vp = ITOV(ip);
	int error;

	ump = VFSTOUFS(vp->v_mount);
	/*
	 * Set up the user quota based on file uid.
	 * EINVAL means that quotas are not enabled.
	 */
	if (ip->i_dquot[USRQUOTA] == NODQUOT &&
	    (error =
		dqget(vp, ip->i_uid, ump, USRQUOTA, &ip->i_dquot[USRQUOTA])) &&
	    error != EINVAL)
		return (error);
	/*
	 * Set up the group quota based on file gid.
	 * EINVAL means that quotas are not enabled.
	 */
	if (ip->i_dquot[GRPQUOTA] == NODQUOT &&
	    (error =
		dqget(vp, ip->i_gid, ump, GRPQUOTA, &ip->i_dquot[GRPQUOTA])) &&
	    error != EINVAL)
		return (error);
	return (0);
}

/*
 * Update disk usage, and take corrective action.
 */
int
chkdq(ip, change, cred, flags)
	register struct inode *ip;
	long change;
	struct ucred *cred;
	int flags;
{
	register struct dquot *dq;
	register int i;
	int ncurblocks, error;

#ifdef DIAGNOSTIC
	if ((flags & CHOWN) == 0)
		chkdquot(ip);
#endif
	if (change == 0)
		return (0);
	if (change < 0) {
		for (i = 0; i < MAXQUOTAS; i++) {
			if ((dq = ip->i_dquot[i]) == NODQUOT)
				continue;
			while (dq->dq_flags & DQ_LOCK) {
				dq->dq_flags |= DQ_WANT;
				sleep((caddr_t)dq, PINOD+1);
			}
			ncurblocks = dq->dq_curblocks + change;
			if (ncurblocks >= 0)
				dq->dq_curblocks = ncurblocks;
			else
				dq->dq_curblocks = 0;
			dq->dq_flags &= ~DQ_BLKS;
			dq->dq_flags |= DQ_MOD;
		}
		return (0);
	}
	if ((flags & FORCE) == 0 && cred->cr_uid != 0) {
		for (i = 0; i < MAXQUOTAS; i++) {
			if ((dq = ip->i_dquot[i]) == NODQUOT)
				continue;
			if (error = chkdqchg(ip, change, cred, i))
				return (error);
		}
	}
	for (i = 0; i < MAXQUOTAS; i++) {
		if ((dq = ip->i_dquot[i]) == NODQUOT)
			continue;
		while (dq->dq_flags & DQ_LOCK) {
			dq->dq_flags |= DQ_WANT;
			sleep((caddr_t)dq, PINOD+1);
		}
		dq->dq_curblocks += change;
		dq->dq_flags |= DQ_MOD;
	}
	return (0);
}

/*
 * Check for a valid change to a users allocation.
 * Issue an error message if appropriate.
 */
int
chkdqchg(ip, change, cred, type)
	struct inode *ip;
	long change;
	struct ucred *cred;
	int type;
{
	register struct dquot *dq = ip->i_dquot[type];
	long ncurblocks = dq->dq_curblocks + change;

	/*
	 * If user would exceed their hard limit, disallow space allocation.
	 */
	if (ncurblocks >= dq->dq_bhardlimit && dq->dq_bhardlimit) {
		if ((dq->dq_flags & DQ_BLKS) == 0 &&
		    ip->i_uid == cred->cr_uid) {
			uprintf("\n%s: write failed, %s disk limit reached\n",
			    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
			    quotatypes[type]);
			dq->dq_flags |= DQ_BLKS;
		}
		return (EDQUOT);
	}
	/*
	 * If user is over their soft limit for too long, disallow space
	 * allocation. Reset time limit as they cross their soft limit.
	 */
	if (ncurblocks >= dq->dq_bsoftlimit && dq->dq_bsoftlimit) {
		if (dq->dq_curblocks < dq->dq_bsoftlimit) {
			dq->dq_btime = time.tv_sec +
			    VFSTOUFS(ITOV(ip)->v_mount)->um_btime[type];
			if (ip->i_uid == cred->cr_uid)
				uprintf("\n%s: warning, %s %s\n",
				    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
				    quotatypes[type], "disk quota exceeded");
			return (0);
		}
		if (time.tv_sec > dq->dq_btime) {
			if ((dq->dq_flags & DQ_BLKS) == 0 &&
			    ip->i_uid == cred->cr_uid) {
				uprintf("\n%s: write failed, %s %s\n",
				    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
				    quotatypes[type],
				    "disk quota exceeded for too long");
				dq->dq_flags |= DQ_BLKS;
			}
			return (EDQUOT);
		}
	}
	return (0);
}

/*
 * Check the inode limit, applying corrective action.
 */
int
chkiq(ip, change, cred, flags)
	register struct inode *ip;
	long change;
	struct ucred *cred;
	int flags;
{
	register struct dquot *dq;
	register int i;
	int ncurinodes, error;

#ifdef DIAGNOSTIC
	if ((flags & CHOWN) == 0)
		chkdquot(ip);
#endif
	if (change == 0)
		return (0);
	if (change < 0) {
		for (i = 0; i < MAXQUOTAS; i++) {
			if ((dq = ip->i_dquot[i]) == NODQUOT)
				continue;
			while (dq->dq_flags & DQ_LOCK) {
				dq->dq_flags |= DQ_WANT;
				sleep((caddr_t)dq, PINOD+1);
			}
			ncurinodes = dq->dq_curinodes + change;
			if (ncurinodes >= 0)
				dq->dq_curinodes = ncurinodes;
			else
				dq->dq_curinodes = 0;
			dq->dq_flags &= ~DQ_INODS;
			dq->dq_flags |= DQ_MOD;
		}
		return (0);
	}
	if ((flags & FORCE) == 0 && cred->cr_uid != 0) {
		for (i = 0; i < MAXQUOTAS; i++) {
			if ((dq = ip->i_dquot[i]) == NODQUOT)
				continue;
			if (error = chkiqchg(ip, change, cred, i))
				return (error);
		}
	}
	for (i = 0; i < MAXQUOTAS; i++) {
		if ((dq = ip->i_dquot[i]) == NODQUOT)
			continue;
		while (dq->dq_flags & DQ_LOCK) {
			dq->dq_flags |= DQ_WANT;
			sleep((caddr_t)dq, PINOD+1);
		}
		dq->dq_curinodes += change;
		dq->dq_flags |= DQ_MOD;
	}
	return (0);
}

/*
 * Check for a valid change to a users allocation.
 * Issue an error message if appropriate.
 */
int
chkiqchg(ip, change, cred, type)
	struct inode *ip;
	long change;
	struct ucred *cred;
	int type;
{
	register struct dquot *dq = ip->i_dquot[type];
	long ncurinodes = dq->dq_curinodes + change;

	/*
	 * If user would exceed their hard limit, disallow inode allocation.
	 */
	if (ncurinodes >= dq->dq_ihardlimit && dq->dq_ihardlimit) {
		if ((dq->dq_flags & DQ_INODS) == 0 &&
		    ip->i_uid == cred->cr_uid) {
			uprintf("\n%s: write failed, %s inode limit reached\n",
			    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
			    quotatypes[type]);
			dq->dq_flags |= DQ_INODS;
		}
		return (EDQUOT);
	}
	/*
	 * If user is over their soft limit for too long, disallow inode
	 * allocation. Reset time limit as they cross their soft limit.
	 */
	if (ncurinodes >= dq->dq_isoftlimit && dq->dq_isoftlimit) {
		if (dq->dq_curinodes < dq->dq_isoftlimit) {
			dq->dq_itime = time.tv_sec +
			    VFSTOUFS(ITOV(ip)->v_mount)->um_itime[type];
			if (ip->i_uid == cred->cr_uid)
				uprintf("\n%s: warning, %s %s\n",
				    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
				    quotatypes[type], "inode quota exceeded");
			return (0);
		}
		if (time.tv_sec > dq->dq_itime) {
			if ((dq->dq_flags & DQ_INODS) == 0 &&
			    ip->i_uid == cred->cr_uid) {
				uprintf("\n%s: write failed, %s %s\n",
				    ITOV(ip)->v_mount->mnt_stat.f_mntonname,
				    quotatypes[type],
				    "inode quota exceeded for too long");
				dq->dq_flags |= DQ_INODS;
			}
			return (EDQUOT);
		}
	}
	return (0);
}

#ifdef DIAGNOSTIC
/*
 * On filesystems with quotas enabled, it is an error for a file to change
 * size and not to have a dquot structure associated with it.
 */
void
chkdquot(ip)
	register struct inode *ip;
{
	struct ufsmount *ump = VFSTOUFS(ITOV(ip)->v_mount);
	register int i;

	for (i = 0; i < MAXQUOTAS; i++) {
		if (ump->um_quotas[i] == NULLVP ||
		    (ump->um_qflags[i] & (QTF_OPENING|QTF_CLOSING)))
			continue;
		if (ip->i_dquot[i] == NODQUOT) {
			vprint("chkdquot: missing dquot", ITOV(ip));
			panic("missing dquot");
		}
	}
}
#endif

/*
 * Code to process quotactl commands.
 */

/*
 * Q_QUOTAON - set up a quota file for a particular file system.
 */
int
quotaon(p, mp, type, fname)
	struct proc *p;
	struct mount *mp;
	register int type;
	caddr_t fname;
{
	register struct ufsmount *ump = VFSTOUFS(mp);
	register struct vnode *vp, **vpp;
	struct vnode *nextvp;
	struct dquot *dq;
	int error;
	struct nameidata nd;

	vpp = &ump->um_quotas[type];
	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, fname, p);
	if (error = vn_open(&nd, FREAD|FWRITE, 0))
		return (error);
	vp = nd.ni_vp;
	VOP_UNLOCK(vp);
	if (vp->v_type != VREG) {
		(void) vn_close(vp, FREAD|FWRITE, p->p_ucred, p);
		return (EACCES);
	}
	if (vfs_busy(mp)) {
		(void) vn_close(vp, FREAD|FWRITE, p->p_ucred, p);
		return (EBUSY);
	}
	if (*vpp != vp)
		quotaoff(p, mp, type);
	ump->um_qflags[type] |= QTF_OPENING;
	mp->mnt_flag |= MNT_QUOTA;
	vp->v_flag |= VSYSTEM;
	*vpp = vp;
	/*
	 * Save the credential of the process that turned on quotas.
	 * Set up the time limits for this quota.
	 */
	crhold(p->p_ucred);
	ump->um_cred[type] = p->p_ucred;
	ump->um_btime[type] = MAX_DQ_TIME;
	ump->um_itime[type] = MAX_IQ_TIME;
	if (dqget(NULLVP, 0, ump, type, &dq) == 0) {
		if (dq->dq_btime > 0)
			ump->um_btime[type] = dq->dq_btime;
		if (dq->dq_itime > 0)
			ump->um_itime[type] = dq->dq_itime;
		dqrele(NULLVP, dq);
	}
	/*
	 * Search vnodes associated with this mount point,
	 * adding references to quota file being opened.
	 * NB: only need to add dquot's for inodes being modified.
	 */
again:
	for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nextvp) {
		nextvp = vp->v_mntvnodes.le_next;
		if (vp->v_writecount == 0)
			continue;
		if (vget(vp, 1))
			goto again;
		if (error = getinoquota(VTOI(vp))) {
			vput(vp);
			break;
		}
		vput(vp);
		if (vp->v_mntvnodes.le_next != nextvp || vp->v_mount != mp)
			goto again;
	}
	ump->um_qflags[type] &= ~QTF_OPENING;
	if (error)
		quotaoff(p, mp, type);
	vfs_unbusy(mp);
	return (error);
}

/*
 * Q_QUOTAOFF - turn off disk quotas for a filesystem.
 */
int
quotaoff(p, mp, type)
	struct proc *p;
	struct mount *mp;
	register int type;
{
	register struct vnode *vp;
	struct vnode *qvp, *nextvp;
	struct ufsmount *ump = VFSTOUFS(mp);
	register struct dquot *dq;
	register struct inode *ip;
	int error;
	
	if ((mp->mnt_flag & MNT_MPBUSY) == 0)
		panic("quotaoff: not busy");
	if ((qvp = ump->um_quotas[type]) == NULLVP)
		return (0);
	ump->um_qflags[type] |= QTF_CLOSING;
	/*
	 * Search vnodes associated with this mount point,
	 * deleting any references to quota file being closed.
	 */
again:
	for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nextvp) {
		nextvp = vp->v_mntvnodes.le_next;
		if (vget(vp, 1))
			goto again;
		ip = VTOI(vp);
		dq = ip->i_dquot[type];
		ip->i_dquot[type] = NODQUOT;
		dqrele(vp, dq);
		vput(vp);
		if (vp->v_mntvnodes.le_next != nextvp || vp->v_mount != mp)
			goto again;
	}