Problem caused by check_for_locks() calling nfsd_file_put while
holding the cl_lock.
Fix by moving nfsd_file_put to callers of check_for_locks() and serialize
access to nf_putfile using the cl_putfile mutex. nfsd4_release_lockowner
delays calling nfsd_file_put until after releasing the cl_lock.
Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
---
fs/nfsd/filecache.c | 13 +++++++++++++
fs/nfsd/filecache.h | 2 ++
fs/nfsd/nfs4state.c | 46 ++++++++++++++++++++++++++++------------------
fs/nfsd/state.h | 3 +++
4 files changed, 46 insertions(+), 18 deletions(-)
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 2c1b027774d4..4a8ae1e562d2 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -175,6 +175,7 @@ nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval,
if (nf) {
INIT_HLIST_NODE(&nf->nf_node);
INIT_LIST_HEAD(&nf->nf_lru);
+ INIT_LIST_HEAD(&nf->nf_putfile);
nf->nf_file = NULL;
nf->nf_cred = get_current_cred();
nf->nf_net = net;
@@ -315,6 +316,18 @@ nfsd_file_put(struct nfsd_file *nf)
nfsd_file_gc();
}
+void
+nfsd_file_bulk_put(struct list_head *putlist)
+{
+ struct nfsd_file *nf;
+
+ while (!list_empty(putlist)) {
+ nf = list_first_entry(putlist, struct nfsd_file, nf_putfile);
+ list_del_init(&nf->nf_putfile);
+ nfsd_file_put(nf);
+ }
+}
+
struct nfsd_file *
nfsd_file_get(struct nfsd_file *nf)
{
diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h
index 435ceab27897..2d775fea431a 100644
--- a/fs/nfsd/filecache.h
+++ b/fs/nfsd/filecache.h
@@ -46,6 +46,7 @@ struct nfsd_file {
refcount_t nf_ref;
unsigned char nf_may;
struct nfsd_file_mark *nf_mark;
+ struct list_head nf_putfile;
};
int nfsd_file_cache_init(void);
@@ -54,6 +55,7 @@ void nfsd_file_cache_shutdown(void);
int nfsd_file_cache_start_net(struct net *net);
void nfsd_file_cache_shutdown_net(struct net *net);
void nfsd_file_put(struct nfsd_file *nf);
+void nfsd_file_bulk_put(struct list_head *putlist);
struct nfsd_file *nfsd_file_get(struct nfsd_file *nf);
void nfsd_file_close_inode_sync(struct inode *inode);
bool nfsd_file_is_cached(struct inode *inode);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 234e852fcdfa..ef533707d198 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -80,7 +80,7 @@ static u64 current_sessionid = 1;
#define CLOSE_STATEID(stateid) (!memcmp((stateid), &close_stateid, sizeof(stateid_t)))
/* forward declarations */
-static bool check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner);
+static bool check_for_locks(struct nfsd_file *nf, struct nfs4_lockowner *lowner);
static void nfs4_free_ol_stateid(struct nfs4_stid *stid);
void nfsd4_end_grace(struct nfsd_net *nn);
static void _free_cpntf_state_locked(struct nfsd_net *nn, struct nfs4_cpntf_state *cps);
@@ -2015,6 +2015,7 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name)
INIT_LIST_HEAD(&clp->async_copies);
spin_lock_init(&clp->async_lock);
spin_lock_init(&clp->cl_lock);
+ mutex_init(&clp->cl_putfile);
rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table");
return clp;
err_no_hashtbl:
@@ -6139,6 +6140,7 @@ static __be32
nfsd4_free_lock_stateid(stateid_t *stateid, struct nfs4_stid *s)
{
struct nfs4_ol_stateid *stp = openlockstateid(s);
+ struct nfsd_file *nf;
__be32 ret;
ret = nfsd4_lock_ol_stateid(stp);
@@ -6150,9 +6152,14 @@ nfsd4_free_lock_stateid(stateid_t *stateid, struct nfs4_stid *s)
goto out;
ret = nfserr_locks_held;
- if (check_for_locks(stp->st_stid.sc_file,
- lockowner(stp->st_stateowner)))
- goto out;
+ nf = find_any_file(stp->st_stid.sc_file);
+ if (nf) {
+ if (check_for_locks(nf, lockowner(stp->st_stateowner))) {
+ nfsd_file_put(nf);
+ goto out;
+ }
+ nfsd_file_put(nf);
+ }
release_lock_stateid(stp);
ret = nfs_ok;
@@ -7266,20 +7273,13 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
* false: no locks held by lockowner
*/
static bool
-check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner)
+check_for_locks(struct nfsd_file *nf, struct nfs4_lockowner *lowner)
{
struct file_lock *fl;
int status = false;
- struct nfsd_file *nf = find_any_file(fp);
struct inode *inode;
struct file_lock_context *flctx;
- if (!nf) {
- /* Any valid lock stateid should have some sort of access */
- WARN_ON_ONCE(1);
- return status;
- }
-
inode = locks_inode(nf->nf_file);
flctx = inode->i_flctx;
@@ -7293,7 +7293,6 @@ check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner)
}
spin_unlock(&flctx->flc_lock);
}
- nfsd_file_put(nf);
return status;
}
@@ -7313,6 +7312,8 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
struct nfs4_client *clp;
LIST_HEAD (reaplist);
+ LIST_HEAD(putlist);
+ struct nfsd_file *nf;
dprintk("nfsd4_release_lockowner clientid: (%08x/%08x):\n",
clid->cl_boot, clid->cl_id);
@@ -7323,6 +7324,7 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
clp = cstate->clp;
/* Find the matching lock stateowner */
+ mutex_lock(&clp->cl_putfile);
spin_lock(&clp->cl_lock);
list_for_each_entry(sop, &clp->cl_ownerstr_hashtbl[hashval],
so_strhash) {
@@ -7333,18 +7335,24 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
/* see if there are still any locks associated with it */
lo = lockowner(sop);
list_for_each_entry(stp, &sop->so_stateids, st_perstateowner) {
- if (check_for_locks(stp->st_stid.sc_file, lo)) {
- status = nfserr_locks_held;
- spin_unlock(&clp->cl_lock);
- return status;
+ nf = find_any_file(stp->st_stid.sc_file);
+ if (nf) {
+ list_add(&nf->nf_putfile, &putlist);
+ if (check_for_locks(nf, lo)) {
+ status = nfserr_locks_held;
+ spin_unlock(&clp->cl_lock);
+ nfsd_file_bulk_put(&putlist);
+ mutex_unlock(&clp->cl_putfile);
+ return status;
+ }
}
}
-
nfs4_get_stateowner(sop);
break;
}
if (!lo) {
spin_unlock(&clp->cl_lock);
+ mutex_unlock(&clp->cl_putfile);
return status;
}
@@ -7357,6 +7365,8 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
put_ol_stateid_locked(stp, &reaplist);
}
spin_unlock(&clp->cl_lock);
+ nfsd_file_bulk_put(&putlist);
+ mutex_unlock(&clp->cl_putfile);
free_ol_stateid_reaplist(&reaplist);
remove_blocked_locks(lo);
nfs4_put_stateowner(&lo->lo_owner);
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 95457cfd37fc..c452d719369d 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -385,6 +385,9 @@ struct nfs4_client {
struct list_head async_copies; /* list of async copies */
spinlock_t async_lock; /* lock for async copies */
atomic_t cl_cb_inflight; /* Outstanding callbacks */
+
+ /* serialize access to nf_putfile */
+ struct mutex cl_putfile;
};
/* struct nfs4_client_reset
--
2.9.5
