nfsd: Add reference counting to the lock and open stateids

When we remove the client_mutex, we'll need to be able to ensure that
these objects aren't destroyed while we're not holding locks.

Add a ->free() callback to the struct nfs4_stid, so that we can
release a reference to the stid without caring about the contents.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Trond Myklebust 2014-07-29 21:34:06 -04:00 committed by J. Bruce Fields
parent b3fbfe0e7a
commit 6011695da2
3 changed files with 58 additions and 50 deletions

View File

@ -905,7 +905,7 @@ static void nfsd4_cb_recall_release(void *calldata)
spin_lock(&clp->cl_lock);
list_del(&cb->cb_per_client);
spin_unlock(&clp->cl_lock);
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
}
}

View File

@ -71,6 +71,7 @@ static u64 current_sessionid = 1;
/* forward declarations */
static bool check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner);
static void nfs4_free_ol_stateid(struct nfs4_stid *stid);
/* Locking: */
@ -463,8 +464,8 @@ static void nfs4_file_put_access(struct nfs4_file *fp, u32 access)
__nfs4_file_put_access(fp, O_RDONLY);
}
static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct
kmem_cache *slab)
static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
struct kmem_cache *slab)
{
struct idr *stateids = &cl->cl_stateids;
struct nfs4_stid *stid;
@ -500,7 +501,26 @@ out_free:
static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp)
{
return openlockstateid(nfs4_alloc_stid(clp, stateid_slab));
struct nfs4_stid *stid;
struct nfs4_ol_stateid *stp;
stid = nfs4_alloc_stid(clp, stateid_slab);
if (!stid)
return NULL;
stp = openlockstateid(stid);
stp->st_stid.sc_free = nfs4_free_ol_stateid;
return stp;
}
static void nfs4_free_deleg(struct nfs4_stid *stid)
{
struct nfs4_delegation *dp = delegstateid(stid);
if (dp->dl_file)
put_nfs4_file(dp->dl_file);
kmem_cache_free(deleg_slab, stid);
atomic_long_dec(&num_delegations);
}
/*
@ -594,6 +614,8 @@ alloc_init_deleg(struct nfs4_client *clp, struct svc_fh *current_fh)
dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
if (dp == NULL)
goto out_dec;
dp->dl_stid.sc_free = nfs4_free_deleg;
/*
* delegation seqid's are never incremented. The 4.1 special
* meaning of seqid 0 isn't meaningful, really, but let's avoid
@ -611,28 +633,15 @@ out_dec:
return NULL;
}
static void remove_stid(struct nfs4_stid *s)
{
struct idr *stateids = &s->sc_client->cl_stateids;
idr_remove(stateids, s->sc_stateid.si_opaque.so_id);
}
static void nfs4_free_stid(struct kmem_cache *slab, struct nfs4_stid *s)
{
kmem_cache_free(slab, s);
}
void
nfs4_put_delegation(struct nfs4_delegation *dp)
nfs4_put_stid(struct nfs4_stid *s)
{
if (atomic_dec_and_test(&dp->dl_stid.sc_count)) {
if (dp->dl_file)
put_nfs4_file(dp->dl_file);
remove_stid(&dp->dl_stid);
nfs4_free_stid(deleg_slab, &dp->dl_stid);
atomic_long_dec(&num_delegations);
}
struct nfs4_client *clp = s->sc_client;
if (!atomic_dec_and_test(&s->sc_count))
return;
idr_remove(&clp->cl_stateids, s->sc_stateid.si_opaque.so_id);
s->sc_free(s);
}
static void nfs4_put_deleg_lease(struct nfs4_file *fp)
@ -689,7 +698,7 @@ static void destroy_delegation(struct nfs4_delegation *dp)
spin_lock(&state_lock);
unhash_delegation_locked(dp);
spin_unlock(&state_lock);
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
}
static void revoke_delegation(struct nfs4_delegation *dp)
@ -699,7 +708,7 @@ static void revoke_delegation(struct nfs4_delegation *dp)
WARN_ON(!list_empty(&dp->dl_recall_lru));
if (clp->cl_minorversion == 0)
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
else {
dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID;
spin_lock(&clp->cl_lock);
@ -885,17 +894,14 @@ static void unhash_generic_stateid(struct nfs4_ol_stateid *stp)
list_del(&stp->st_perstateowner);
}
static void close_generic_stateid(struct nfs4_ol_stateid *stp)
static void nfs4_free_ol_stateid(struct nfs4_stid *stid)
{
release_all_access(stp);
}
struct nfs4_ol_stateid *stp = openlockstateid(stid);
static void free_generic_stateid(struct nfs4_ol_stateid *stp)
{
release_all_access(stp);
if (stp->st_file)
put_nfs4_file(stp->st_file);
remove_stid(&stp->st_stid);
nfs4_free_stid(stateid_slab, &stp->st_stid);
kmem_cache_free(stateid_slab, stid);
}
static void __release_lock_stateid(struct nfs4_ol_stateid *stp)
@ -908,8 +914,7 @@ static void __release_lock_stateid(struct nfs4_ol_stateid *stp)
file = find_any_file(stp->st_file);
if (file)
filp_close(file, (fl_owner_t)lockowner(stp->st_stateowner));
close_generic_stateid(stp);
free_generic_stateid(stp);
nfs4_put_stid(&stp->st_stid);
}
static void unhash_lockowner(struct nfs4_lockowner *lo)
@ -966,13 +971,12 @@ static void unhash_open_stateid(struct nfs4_ol_stateid *stp)
{
unhash_generic_stateid(stp);
release_open_stateid_locks(stp);
close_generic_stateid(stp);
}
static void release_open_stateid(struct nfs4_ol_stateid *stp)
{
unhash_open_stateid(stp);
free_generic_stateid(stp);
nfs4_put_stid(&stp->st_stid);
}
static void unhash_openowner(struct nfs4_openowner *oo)
@ -993,7 +997,7 @@ static void release_last_closed_stateid(struct nfs4_openowner *oo)
struct nfs4_ol_stateid *s = oo->oo_last_closed_stid;
if (s) {
free_generic_stateid(s);
nfs4_put_stid(&s->st_stid);
oo->oo_last_closed_stid = NULL;
}
}
@ -1467,12 +1471,12 @@ destroy_client(struct nfs4_client *clp)
while (!list_empty(&reaplist)) {
dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
}
while (!list_empty(&clp->cl_revoked)) {
dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
}
while (!list_empty(&clp->cl_openowners)) {
oo = list_entry(clp->cl_openowners.next, struct nfs4_openowner, oo_perclient);
@ -3588,7 +3592,7 @@ out_unlock:
spin_unlock(&state_lock);
out:
if (status) {
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
return ERR_PTR(status);
}
return dp;
@ -3818,7 +3822,7 @@ void nfsd4_cleanup_open_state(struct nfsd4_open *open, __be32 status)
if (open->op_file)
nfsd4_free_file(open->op_file);
if (open->op_stp)
free_generic_stateid(open->op_stp);
nfs4_put_stid(&open->op_stp->st_stid);
}
__be32
@ -4266,7 +4270,7 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
spin_lock(&cl->cl_lock);
list_del_init(&dp->dl_recall_lru);
spin_unlock(&cl->cl_lock);
nfs4_put_delegation(dp);
nfs4_put_stid(s);
ret = nfs_ok;
break;
default:
@ -4477,19 +4481,22 @@ static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s)
unhash_open_stateid(s);
if (clp->cl_minorversion) {
free_generic_stateid(s);
if (list_empty(&oo->oo_owner.so_stateids))
release_openowner(oo);
nfs4_put_stid(&s->st_stid);
} else {
/*
* In the 4.0 case we need to keep the owners around a
* little while to handle CLOSE replay. We still do need
* to release any file access that is held by them
* before returning however.
*/
release_all_access(s);
if (s->st_file) {
put_nfs4_file(s->st_file);
s->st_file = NULL;
}
oo->oo_last_closed_stid = s;
/*
* In the 4.0 case we need to keep the owners around a
* little while to handle CLOSE replay.
*/
if (list_empty(&oo->oo_owner.so_stateids))
move_to_close_lru(oo, clp->net);
}
@ -5665,7 +5672,7 @@ nfs4_state_shutdown_net(struct net *net)
list_for_each_safe(pos, next, &reaplist) {
dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
nfs4_put_delegation(dp);
nfs4_put_stid(&dp->dl_stid);
}
nfsd4_client_tracking_exit(net);

View File

@ -85,6 +85,7 @@ struct nfs4_stid {
unsigned char sc_type;
stateid_t sc_stateid;
struct nfs4_client *sc_client;
void (*sc_free)(struct nfs4_stid *);
};
struct nfs4_delegation {
@ -429,6 +430,7 @@ extern __be32 nfs4_preprocess_stateid_op(struct net *net,
stateid_t *stateid, int flags, struct file **filp);
extern void nfs4_lock_state(void);
extern void nfs4_unlock_state(void);
void nfs4_put_stid(struct nfs4_stid *s);
void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
extern void nfs4_release_reclaim(struct nfsd_net *);
extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(const char *recdir,
@ -446,7 +448,6 @@ extern int nfsd4_create_callback_queue(void);
extern void nfsd4_destroy_callback_queue(void);
extern void nfsd4_shutdown_callback(struct nfs4_client *);
extern void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp);
extern void nfs4_put_delegation(struct nfs4_delegation *dp);
extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name,
struct nfsd_net *nn);
extern bool nfs4_has_reclaimed_state(const char *name, struct nfsd_net *nn);