/*
* Helper function to handle quota request from slave.
*
* \param env - is the environment passed by the caller
* \param lqe - is the lquota_entry subject to the quota request
* \param qmt - is the master device
* \param uuid - is the uuid associated with the slave
* \param qb_flags - are the quota request flags as packed in the quota_body
* \param qb_count - is the amount of quota space the slave wants to
* acquire/release
* \param qb_usage - is the current space usage on the slave
* \param repbody - is the quota_body of reply
*
* \retval 0 : success
* \retval -EDQUOT : out of quota
* -EINPROGRESS : inform client to retry write/create
* -ve : other appropriate errors
*/
int qmt_dqacq0(const struct lu_env *env, struct lquota_entry *lqe,
struct qmt_device *qmt, struct obd_uuid *uuid, __u32 qb_flags,
__u64 qb_count, __u64 qb_usage, struct quota_body *repbody)
{
struct qmt_thread_info *qti = qmt_info(env);
__u64 now, count;
struct dt_object *slv_obj = NULL;
__u64 slv_granted, slv_granted_bck;
struct thandle *th = NULL;
int rc, ret;
ENTRY;
LASSERT(uuid != NULL);
/* initialize reply */
memset(repbody, 0, sizeof(*repbody));
memcpy(&repbody->qb_id, &lqe->lqe_id, sizeof(repbody->qb_id));
if (OBD_FAIL_CHECK(OBD_FAIL_QUOTA_RECOVERABLE_ERR))
RETURN(-cfs_fail_val);
/* look-up index file associated with acquiring slave */
slv_obj = lquota_disk_slv_find(env, qmt->qmt_child, LQE_ROOT(lqe),
lu_object_fid(&LQE_GLB_OBJ(lqe)->do_lu),
uuid);
if (IS_ERR(slv_obj))
GOTO(out, rc = PTR_ERR(slv_obj));
/* pack slave fid in reply just for sanity check */
memcpy(&repbody->qb_slv_fid, lu_object_fid(&slv_obj->do_lu),
sizeof(struct lu_fid));
/* allocate & start transaction with enough credits to update
* global & slave indexes */
th = qmt_trans_start_with_slv(env, lqe, slv_obj, &qti->qti_restore);
if (IS_ERR(th))
GOTO(out, rc = PTR_ERR(th));
lqe_write_lock(lqe);
LQUOTA_DEBUG(lqe, "dqacq starts uuid:%s flags:0x%x wanted:"LPU64
" usage:"LPU64, obd_uuid2str(uuid), qb_flags, qb_count,
qb_usage);
/* Legal race, limits have been removed on master, but slave didn't
* receive the change yet. Just return EINPROGRESS until the slave gets
* notified. */
if (!lqe->lqe_enforced && !req_is_rel(qb_flags))
GOTO(out_locked, rc = -ESRCH);
/* recompute qunit in case it was never initialized */
qmt_revalidate(env, lqe);
/* slave just wants to acquire per-ID lock */
if (req_is_acq(qb_flags) && qb_count == 0)
GOTO(out_locked, rc = 0);
/* fetch how much quota space is already granted to this slave */
rc = qmt_slv_read(env, lqe, slv_obj, &slv_granted);
if (rc) {
LQUOTA_ERROR(lqe, "Failed to get granted for slave %s, rc=%d",
obd_uuid2str(uuid), rc);
GOTO(out_locked, rc);
}
/* recall how much space this slave currently owns in order to restore
* it in case of failure */
slv_granted_bck = slv_granted;
/* record current time for soft limit & grace time management */
now = (__u64)cfs_time_current_sec();
if (req_is_rel(qb_flags)) {
/* Slave would like to release quota space */
if (slv_granted < qb_count ||
lqe->lqe_granted < qb_count) {
/* can't release more than granted */
LQUOTA_ERROR(lqe, "Release too much! uuid:%s release:"
LPU64" granted:"LPU64", total:"LPU64,
obd_uuid2str(uuid), qb_count,
slv_granted, lqe->lqe_granted);
GOTO(out_locked, rc = -EINVAL);
}
repbody->qb_count = qb_count;
/* put released space back to global pool */
QMT_REL(lqe, slv_granted, qb_count);
GOTO(out_write, rc = 0);
}
if (req_has_rep(qb_flags) && slv_granted < qb_usage) {
/* Slave is reporting space usage in quota request and it turns
* out to be using more quota space than owned, so we adjust
* granted space regardless of the current state of affairs */
repbody->qb_count = qb_usage - slv_granted;
QMT_GRANT(lqe, slv_granted, repbody->qb_count);
}
if (!req_is_acq(qb_flags) && !req_is_preacq(qb_flags))
GOTO(out_write, rc = 0);
qmt_adjust_edquot(lqe, now);
if (lqe->lqe_edquot)
/* no hope to claim further space back */
GOTO(out_write, rc = -EDQUOT);
if (qmt_space_exhausted(lqe, now)) {
/* might have some free space once rebalancing is completed */
rc = req_is_acq(qb_flags) ? -EINPROGRESS : -EDQUOT;
GOTO(out_write, rc);
}
if (req_is_preacq(qb_flags)) {
/* slave would like to pre-acquire quota space. To do so, it
* reports in qb_count how much spare quota space it owns and we
* can grant back quota space which is consistent with qunit
* value. */
if (qb_count >= lqe->lqe_qunit)
/* slave already own the maximum it should */
GOTO(out_write, rc = 0);
count = qmt_alloc_expand(lqe, slv_granted, qb_count);
if (count == 0)
GOTO(out_write, rc = -EDQUOT);
repbody->qb_count += count;
QMT_GRANT(lqe, slv_granted, count);
GOTO(out_write, rc = 0);
}
/* processing acquire request with clients waiting */
if (lqe->lqe_hardlimit != 0 &&
lqe->lqe_granted + qb_count > lqe->lqe_hardlimit) {
/* cannot grant as much as asked, but can still afford to grant
* some quota space back */
count = lqe->lqe_hardlimit - lqe->lqe_granted;
repbody->qb_count += count;
QMT_GRANT(lqe, slv_granted, count);
GOTO(out_write, rc = 0);
}
/* Whouhou! we can satisfy the slave request! */
repbody->qb_count += qb_count;
QMT_GRANT(lqe, slv_granted, qb_count);
/* Try to expand the acquired count for DQACQ */
count = qmt_alloc_expand(lqe, slv_granted, 0);
if (count != 0) {
/* can even grant more than asked, it is like xmas ... */
repbody->qb_count += count;
QMT_GRANT(lqe, slv_granted, count);
GOTO(out_write, rc = 0);
}
GOTO(out_write, rc = 0);
out_write:
if (repbody->qb_count == 0)
GOTO(out_locked, rc);
/* start/stop grace timer if required */
if (lqe->lqe_softlimit != 0) {
if (lqe->lqe_granted > lqe->lqe_softlimit &&
lqe->lqe_gracetime == 0)
/* first time over soft limit, let's start grace
* timer */
lqe->lqe_gracetime = now + qmt_lqe_grace(lqe);
else if (lqe->lqe_granted <= lqe->lqe_softlimit &&
lqe->lqe_gracetime != 0)
/* Clear grace timer */
lqe->lqe_gracetime = 0;
}
/* Update slave index first since it is easier to roll back */
ret = qmt_slv_write(env, th, lqe, slv_obj, LQUOTA_BUMP_VER,
&repbody->qb_slv_ver, slv_granted);
if (ret) {
/* restore initial quota settings */
qmt_restore(lqe, &qti->qti_restore);
/* reset qb_count */
repbody->qb_count = 0;
GOTO(out_locked, rc = ret);
}
/* Update global index, no version bump needed */
ret = qmt_glb_write(env, th, lqe, 0, NULL);
if (ret) {
rc = ret;
/* restore initial quota settings */
qmt_restore(lqe, &qti->qti_restore);
/* reset qb_count */
repbody->qb_count = 0;
/* restore previous granted value */
ret = qmt_slv_write(env, th, lqe, slv_obj, 0, NULL,
slv_granted_bck);
if (ret) {
LQUOTA_ERROR(lqe, "failed to restore initial slave "
"value rc:%d ret%d", rc, ret);
LBUG();
}
qmt_adjust_edquot(lqe, now);
GOTO(out_locked, rc);
}
/* Total granted has been changed, let's try to adjust the qunit
* size according to the total granted & limits. */
qmt_adjust_qunit(env, lqe);
/* clear/set edquot flag and notify slaves via glimpse if needed */
qmt_adjust_edquot(lqe, now);
out_locked:
LQUOTA_DEBUG(lqe, "dqacq ends count:"LPU64" ver:"LPU64" rc:%d",
repbody->qb_count, repbody->qb_slv_ver, rc);
lqe_write_unlock(lqe);
out:
if (th != NULL && !IS_ERR(th))
dt_trans_stop(env, qmt->qmt_child, th);
if (slv_obj != NULL && !IS_ERR(slv_obj))
lu_object_put(env, &slv_obj->do_lu);
if ((req_is_acq(qb_flags) || req_is_preacq(qb_flags)) &&
OBD_FAIL_CHECK(OBD_FAIL_QUOTA_EDQUOT)) {
/* introduce inconsistency between granted value in slave index
* and slave index copy of slave */
repbody->qb_count = 0;
rc = -EDQUOT;
}
RETURN(rc);
}
/**
* Adjust quota space (by acquiring or releasing) hold by the quota slave.
* This function is called after each quota request completion and during
* reintegration in order to report usage or re-acquire quota locks.
* Space adjustment is aborted if there is already a quota request in flight
* for this ID.
*
* \param env - the environment passed by the caller
* \param lqe - is the qid entry to be processed
*
* \retval 0 on success, appropriate errors on failure
*/
int qsd_adjust(const struct lu_env *env, struct lquota_entry *lqe)
{
struct qsd_thread_info *qti = qsd_info(env);
struct quota_body *qbody = &qti->qti_body;
struct qsd_instance *qsd;
struct qsd_qtype_info *qqi;
int rc;
bool intent = false;
ENTRY;
memset(qbody, 0, sizeof(*qbody));
rc = qsd_ready(lqe, &qbody->qb_glb_lockh);
if (rc) {
/* add to adjust list again to trigger adjustment later when
* slave is ready */
LQUOTA_DEBUG(lqe, "delaying adjustment since qsd isn't ready");
qsd_adjust_schedule(lqe, true, false);
RETURN(0);
}
qqi = lqe2qqi(lqe);
qsd = qqi->qqi_qsd;
lqe_write_lock(lqe);
/* fill qb_count & qb_flags */
if (!qsd_calc_adjust(lqe, qbody)) {
lqe_write_unlock(lqe);
LQUOTA_DEBUG(lqe, "no adjustment required");
RETURN(0);
}
/* only 1 quota request in flight for a given ID is allowed */
rc = qsd_request_enter(lqe);
if (rc) {
/* already a request in flight, space adjustment will be run
* again on request completion */
lqe_write_unlock(lqe);
RETURN(0);
}
if (req_is_rel(qbody->qb_flags))
lqe->lqe_pending_rel = qbody->qb_count;
lustre_handle_copy(&qti->qti_lockh, &lqe->lqe_lockh);
lqe_write_unlock(lqe);
/* hold a refcount until completion */
lqe_getref(lqe);
/* fill other quota body fields */
qbody->qb_fid = qqi->qqi_fid;
qbody->qb_id = lqe->lqe_id;
if (req_is_acq(qbody->qb_flags) || req_is_preacq(qbody->qb_flags)) {
/* check whether we own a valid lock for this ID */
rc = qsd_id_lock_match(&qti->qti_lockh, &qbody->qb_lockh);
if (rc) {
memset(&qti->qti_lockh, 0, sizeof(qti->qti_lockh));
if (req_is_preacq(qbody->qb_flags)) {
if (req_has_rep(qbody->qb_flags))
/* still want to report usage */
qbody->qb_flags = QUOTA_DQACQ_FL_REPORT;
else
/* no pre-acquire if no per-ID lock */
GOTO(out, rc = -ENOLCK);
} else {
/* no lock found, should use intent */
intent = true;
}
} else if (req_is_acq(qbody->qb_flags) &&
qbody->qb_count == 0) {
/* found cached lock, no need to acquire */
GOTO(out, rc = 0);
}
} else {
/* release and report don't need a per-ID lock */
memset(&qti->qti_lockh, 0, sizeof(qti->qti_lockh));
}
if (!intent) {
rc = qsd_send_dqacq(env, qsd->qsd_exp, qbody, false,
qsd_req_completion, qqi, &qti->qti_lockh,
lqe);
} else {
struct lquota_lvb *lvb;
OBD_ALLOC_PTR(lvb);
if (lvb == NULL)
GOTO(out, rc = -ENOMEM);
rc = qsd_intent_lock(env, qsd->qsd_exp, qbody, false,
IT_QUOTA_DQACQ, qsd_req_completion,
qqi, lvb, (void *)lqe);
}
/* the completion function will be called by qsd_send_dqacq or
* qsd_intent_lock */
RETURN(rc);
out:
qsd_req_completion(env, qqi, qbody, NULL, &qti->qti_lockh, NULL, lqe,
rc);
return rc;
}
