/*
* Flush all entries from the cache for a particular vnode.
*/
static int
dqflush(struct vnode *vp)
{
struct dquot *dq, *nextdq;
struct dqhash *dqh;
int error;
/*
* Move all dquot's that used to refer to this quota
* file off their hash chains (they will eventually
* fall off the head of the free list and be re-used).
*/
error = 0;
DQH_LOCK();
for (dqh = &dqhashtbl[dqhash]; dqh >= dqhashtbl; dqh--) {
for (dq = LIST_FIRST(dqh); dq; dq = nextdq) {
nextdq = LIST_NEXT(dq, dq_hash);
if (dq->dq_ump->um_quotas[dq->dq_type] != vp)
continue;
if (dq->dq_cnt)
error = EBUSY;
else {
LIST_REMOVE(dq, dq_hash);
dq->dq_ump = NULL;
}
}
}
DQH_UNLOCK();
return (error);
}
/*
* Flush all entries from the cache for a particular vnode.
*/
static void
dqflush(struct vnode *vp)
{
struct dquot *dq, *nextdq;
struct dqhash *dqh;
/*
* Move all dquot's that used to refer to this quota
* file off their hash chains (they will eventually
* fall off the head of the free list and be re-used).
*/
DQH_LOCK();
for (dqh = &dqhashtbl[dqhash]; dqh >= dqhashtbl; dqh--) {
for (dq = LIST_FIRST(dqh); dq; dq = nextdq) {
nextdq = LIST_NEXT(dq, dq_hash);
if (dq->dq_ump->um_quotas[dq->dq_type] != vp)
continue;
if (dq->dq_cnt)
panic("dqflush: stray dquot");
LIST_REMOVE(dq, dq_hash);
dq->dq_ump = (struct ufsmount *)0;
}
}
DQH_UNLOCK();
}
/*
* Release a reference to a dquot.
*/
void
dqrele(struct vnode *vp, struct dquot *dq)
{
if (dq == NODQUOT)
return;
DQH_LOCK();
KASSERT(dq->dq_cnt > 0, ("Lost dq %p reference 1", dq));
if (dq->dq_cnt > 1) {
dq->dq_cnt--;
DQH_UNLOCK();
return;
}
DQH_UNLOCK();
sync:
(void) dqsync(vp, dq);
DQH_LOCK();
KASSERT(dq->dq_cnt > 0, ("Lost dq %p reference 2", dq));
if (--dq->dq_cnt > 0)
{
DQH_UNLOCK();
return;
}
/*
* The dq may become dirty after it is synced but before it is
* put to the free list. Checking the DQ_MOD there without
* locking dq should be safe since no other references to the
* dq exist.
*/
if ((dq->dq_flags & DQ_MOD) != 0) {
dq->dq_cnt++;
DQH_UNLOCK();
goto sync;
}
TAILQ_INSERT_TAIL(&dqfreelist, dq, dq_freelist);
DQH_UNLOCK();
}
/*
* 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);
}
