Ejemplo n.º 1
0
static struct dquot *
dqhashfind(struct dqhash *dqh, u_long id, struct vnode *dqvp)
{
    struct dquot *dq;

    mtx_assert(&dqhlock, MA_OWNED);
    LIST_FOREACH(dq, dqh, dq_hash) {
        if (dq->dq_id != id ||
                dq->dq_ump->um_quotas[dq->dq_type] != dqvp)
            continue;
        /*
         * Cache hit with no references.  Take
         * the structure off the free list.
         */
        if (dq->dq_cnt == 0)
            TAILQ_REMOVE(&dqfreelist, dq, dq_freelist);
        DQREF(dq);
        return (dq);
    }
    return (NODQUOT);
}
Ejemplo n.º 2
0
/*
 * Obtain a dquot structure for the specified identifier and quota file
 * reading the information from the file if necessary.
 */
static int
dqget(struct vnode *vp, u_long id, struct ufsmount *ump, int type,
      struct dquot **dqp)
{
    uint8_t buf[sizeof(struct dqblk64)];
    off_t base, recsize;
    struct dquot *dq, *dq1;
    struct dqhash *dqh;
    struct vnode *dqvp;
    struct iovec aiov;
    struct uio auio;
    int dqvplocked, error;

#ifdef DEBUG_VFS_LOCKS
    if (vp != NULLVP)
        ASSERT_VOP_ELOCKED(vp, "dqget");
#endif

    if (vp != NULLVP && *dqp != NODQUOT) {
        return (0);
    }

    /* XXX: Disallow negative id values to prevent the
    * creation of 100GB+ quota data files.
    */
    if ((int)id < 0)
        return (EINVAL);

    UFS_LOCK(ump);
    dqvp = ump->um_quotas[type];
    if (dqvp == NULLVP || (ump->um_qflags[type] & QTF_CLOSING)) {
        *dqp = NODQUOT;
        UFS_UNLOCK(ump);
        return (EINVAL);
    }
    vref(dqvp);
    UFS_UNLOCK(ump);
    error = 0;
    dqvplocked = 0;

    /*
     * Check the cache first.
     */
    dqh = DQHASH(dqvp, id);
    DQH_LOCK();
    dq = dqhashfind(dqh, id, dqvp);
    if (dq != NULL) {
        DQH_UNLOCK();
hfound:
        DQI_LOCK(dq);
        DQI_WAIT(dq, PINOD+1, "dqget");
        DQI_UNLOCK(dq);
        if (dq->dq_ump == NULL) {
            dqrele(vp, dq);
            dq = NODQUOT;
            error = EIO;
        }
        *dqp = dq;
        if (dqvplocked)
            vput(dqvp);
        else
            vrele(dqvp);
        return (error);
    }

    /*
     * Quota vnode lock is before DQ_LOCK. Acquire dqvp lock there
     * since new dq will appear on the hash chain DQ_LOCKed.
     */
    if (vp != dqvp) {
        DQH_UNLOCK();
        vn_lock(dqvp, LK_SHARED | LK_RETRY);
        dqvplocked = 1;
        DQH_LOCK();
        /*
         * Recheck the cache after sleep for quota vnode lock.
         */
        dq = dqhashfind(dqh, id, dqvp);
        if (dq != NULL) {
            DQH_UNLOCK();
            goto hfound;
        }
    }

    /*
     * Not in cache, allocate a new one or take it from the
     * free list.
     */
    if (TAILQ_FIRST(&dqfreelist) == NODQUOT &&
            numdquot < MAXQUOTAS * desiredvnodes)
        desireddquot += DQUOTINC;
    if (numdquot < desireddquot) {
        numdquot++;
        DQH_UNLOCK();
        dq1 = malloc(sizeof *dq1, M_DQUOT, M_WAITOK | M_ZERO);
        mtx_init(&dq1->dq_lock, "dqlock", NULL, MTX_DEF);
        DQH_LOCK();
        /*
         * Recheck the cache after sleep for memory.
         */
        dq = dqhashfind(dqh, id, dqvp);
        if (dq != NULL) {
            numdquot--;
            DQH_UNLOCK();
            mtx_destroy(&dq1->dq_lock);
            free(dq1, M_DQUOT);
            goto hfound;
        }
        dq = dq1;
    } else {
        if ((dq = TAILQ_FIRST(&dqfreelist)) == NULL) {
            DQH_UNLOCK();
            tablefull("dquot");
            *dqp = NODQUOT;
            if (dqvplocked)
                vput(dqvp);
            else
                vrele(dqvp);
            return (EUSERS);
        }
        if (dq->dq_cnt || (dq->dq_flags & DQ_MOD))
            panic("dqget: free dquot isn't %p", dq);
        TAILQ_REMOVE(&dqfreelist, dq, dq_freelist);
        if (dq->dq_ump != NULL)
            LIST_REMOVE(dq, dq_hash);
    }

    /*
     * Dq is put into hash already locked to prevent parallel
     * usage while it is being read from file.
     */
    dq->dq_flags = DQ_LOCK;
    dq->dq_id = id;
    dq->dq_type = type;
    dq->dq_ump = ump;
    LIST_INSERT_HEAD(dqh, dq, dq_hash);
    DQREF(dq);
    DQH_UNLOCK();

    /*
     * Read the requested quota record from the quota file, performing
     * any necessary conversions.
     */
    if (ump->um_qflags[type] & QTF_64BIT) {
        recsize = sizeof(struct dqblk64);
        base = sizeof(struct dqhdr64);
    } else {
        recsize = sizeof(struct dqblk32);
        base = 0;
    }
    auio.uio_iov = &aiov;
    auio.uio_iovcnt = 1;
    aiov.iov_base = buf;
    aiov.iov_len = recsize;
    auio.uio_resid = recsize;
    auio.uio_offset = base + id * recsize;
    auio.uio_segflg = UIO_SYSSPACE;
    auio.uio_rw = UIO_READ;
    auio.uio_td = (struct thread *)0;

    error = VOP_READ(dqvp, &auio, 0, ump->um_cred[type]);
    if (auio.uio_resid == recsize && error == 0) {
        bzero(&dq->dq_dqb, sizeof(dq->dq_dqb));
    } else {
        if (ump->um_qflags[type] & QTF_64BIT)
            dqb64_dq((struct dqblk64 *)buf, dq);
        else
            dqb32_dq((struct dqblk32 *)buf, dq);
    }
    if (dqvplocked)
        vput(dqvp);
    else
        vrele(dqvp);
    /*
     * I/O error in reading quota file, release
     * quota structure and reflect problem to caller.
     */
    if (error) {
        DQH_LOCK();
        dq->dq_ump = NULL;
        LIST_REMOVE(dq, dq_hash);
        DQH_UNLOCK();
        DQI_LOCK(dq);
        if (dq->dq_flags & DQ_WANT)
            wakeup(dq);
        dq->dq_flags = 0;
        DQI_UNLOCK(dq);
        dqrele(vp, dq);
        *dqp = NODQUOT;
        return (error);
    }
    DQI_LOCK(dq);
    /*
     * Check for no limit to enforce.
     * Initialize time values if necessary.
     */
    if (dq->dq_isoftlimit == 0 && dq->dq_bsoftlimit == 0 &&
            dq->dq_ihardlimit == 0 && dq->dq_bhardlimit == 0)
        dq->dq_flags |= DQ_FAKE;
    if (dq->dq_id != 0) {
        if (dq->dq_btime == 0) {
            dq->dq_btime = time_second + ump->um_btime[type];
            if (dq->dq_bsoftlimit &&
                    dq->dq_curblocks >= dq->dq_bsoftlimit)
                dq->dq_flags |= DQ_MOD;
        }
        if (dq->dq_itime == 0) {
            dq->dq_itime = time_second + ump->um_itime[type];
            if (dq->dq_isoftlimit &&
                    dq->dq_curinodes >= dq->dq_isoftlimit)
                dq->dq_flags |= DQ_MOD;
        }
    }
    DQI_WAKEUP(dq);
    DQI_UNLOCK(dq);
    *dqp = dq;
    return (0);
}
Ejemplo n.º 3
0
/*
 * Obtain a dquot structure for the specified identifier and quota file
 * reading the information from the file if necessary.
 */
static int
ufs_dqget(struct vnode *vp, u_long id, struct ufsmount *ump, int type,
      struct ufs_dquot **dqp)
{
	struct ufs_dquot *dq;
	struct ufs_dqhash *dqh;
	struct vnode *dqvp;
	struct iovec aiov;
	struct uio auio;
	int error;

	dqvp = ump->um_quotas[type];
	if (dqvp == NULLVP || (ump->um_qflags[type] & QTF_CLOSING)) {
		*dqp = NODQUOT;
		return (EINVAL);
	}
	/*
	 * Check the cache first.
	 */
	dqh = DQHASH(dqvp, id);
	LIST_FOREACH(dq, dqh, dq_hash) {
		if (dq->dq_id != id ||
		    dq->dq_ump->um_quotas[dq->dq_type] != dqvp)
			continue;
		/*
		 * Cache hit with no references.  Take
		 * the structure off the free list.
		 */
		if (dq->dq_cnt == 0)
			TAILQ_REMOVE(&ufs_dqfreelist, dq, dq_freelist);
		DQREF(dq);
		*dqp = dq;
		return (0);
	}
	/*
	 * Not in cache, allocate a new one.
	 */
	if (TAILQ_EMPTY(&ufs_dqfreelist) && ufs_numdquot < MAXQUOTAS * desiredvnodes)
		ufs_desireddquot += DQUOTINC;
	if (ufs_numdquot < ufs_desireddquot) {
		dq = (struct ufs_dquot *)
			kmalloc(sizeof *dq, M_DQUOT, M_WAITOK | M_ZERO);
		ufs_numdquot++;
	} else {
		if ((dq = TAILQ_FIRST(&ufs_dqfreelist)) == NULL) {
			tablefull("dquot");
			*dqp = NODQUOT;
			return (EUSERS);
		}
		if (dq->dq_cnt || (dq->dq_flags & DQ_MOD))
			panic("dqget: free dquot isn't");
		TAILQ_REMOVE(&ufs_dqfreelist, dq, dq_freelist);
		if (dq->dq_ump != NULL)
			LIST_REMOVE(dq, dq_hash);
	}
	/*
	 * Initialize the contents of the dquot structure.
	 */
	if (vp != dqvp)
		vn_lock(dqvp, LK_EXCLUSIVE | LK_RETRY);
	LIST_INSERT_HEAD(dqh, dq, dq_hash);
	DQREF(dq);
	dq->dq_flags = DQ_LOCK;
	dq->dq_id = id;
	dq->dq_ump = ump;
	dq->dq_type = type;
	auio.uio_iov = &aiov;
	auio.uio_iovcnt = 1;
	aiov.iov_base = (caddr_t)&dq->dq_dqb;
	aiov.iov_len = sizeof (struct ufs_dqblk);
	auio.uio_resid = sizeof (struct ufs_dqblk);
	auio.uio_offset = (off_t)(id * sizeof (struct ufs_dqblk));
	auio.uio_segflg = UIO_SYSSPACE;
	auio.uio_rw = UIO_READ;
	auio.uio_td = NULL;
	error = VOP_READ(dqvp, &auio, 0, ump->um_cred[type]);
	if (auio.uio_resid == sizeof(struct ufs_dqblk) && error == 0)
		bzero((caddr_t)&dq->dq_dqb, sizeof(struct ufs_dqblk));
	if (vp != dqvp)
		vn_unlock(dqvp);
	if (dq->dq_flags & DQ_WANT)
		wakeup((caddr_t)dq);
	dq->dq_flags = 0;
	/*
	 * I/O error in reading quota file, release
	 * quota structure and reflect problem to caller.
	 */
	if (error) {
		LIST_REMOVE(dq, dq_hash);
		ufs_dqrele(vp, dq);
		*dqp = NODQUOT;
		return (error);
	}
	/*
	 * Check for no limit to enforce.
	 * Initialize time values if necessary.
	 */
	if (dq->dq_isoftlimit == 0 && dq->dq_bsoftlimit == 0 &&
	    dq->dq_ihardlimit == 0 && dq->dq_bhardlimit == 0)
		dq->dq_flags |= DQ_FAKE;
	if (dq->dq_id != 0) {
		if (dq->dq_btime == 0)
			dq->dq_btime = time_second + ump->um_btime[type];
		if (dq->dq_itime == 0)
			dq->dq_itime = time_second + ump->um_itime[type];
	}
	*dqp = dq;
	return (0);
}