Merge branch 'for-3.19' of git://linux-nfs.org/~bfields/linux

[cascardo/linux.git] / fs / nfsd / nfs4state.c

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 4e1d726..3550a9c 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -275,9 +275,11 @@ opaque_hashval(const void *ptr, int nbytes)
        return x;
 }
 
-static void nfsd4_free_file(struct nfs4_file *f)
+static void nfsd4_free_file_rcu(struct rcu_head *rcu)
 {
-       kmem_cache_free(file_slab, f);
+       struct nfs4_file *fp = container_of(rcu, struct nfs4_file, fi_rcu);
+
+       kmem_cache_free(file_slab, fp);
 }
 
 static inline void
@@ -286,9 +288,10 @@ put_nfs4_file(struct nfs4_file *fi)
        might_lock(&state_lock);
 
        if (atomic_dec_and_lock(&fi->fi_ref, &state_lock)) {
-               hlist_del(&fi->fi_hash);
+               hlist_del_rcu(&fi->fi_hash);
                spin_unlock(&state_lock);
-               nfsd4_free_file(fi);
+               WARN_ON_ONCE(!list_empty(&fi->fi_delegations));
+               call_rcu(&fi->fi_rcu, nfsd4_free_file_rcu);
        }
 }
 
@@ -1440,7 +1443,7 @@ static void init_session(struct svc_rqst *rqstp, struct nfsd4_session *new, stru
        list_add(&new->se_perclnt, &clp->cl_sessions);
        spin_unlock(&clp->cl_lock);
 
-       if (cses->flags & SESSION4_BACK_CHAN) {
+       {
                struct sockaddr *sa = svc_addr(rqstp);
                /*
                 * This is a little silly; with sessions there's no real
@@ -1711,15 +1714,14 @@ static int copy_cred(struct svc_cred *target, struct svc_cred *source)
        return 0;
 }
 
-static long long
+static int
 compare_blob(const struct xdr_netobj *o1, const struct xdr_netobj *o2)
 {
-       long long res;
-
-       res = o1->len - o2->len;
-       if (res)
-               return res;
-       return (long long)memcmp(o1->data, o2->data, o1->len);
+       if (o1->len < o2->len)
+               return -1;
+       if (o1->len > o2->len)
+               return 1;
+       return memcmp(o1->data, o2->data, o1->len);
 }
 
 static int same_name(const char *n1, const char *n2)
@@ -1907,7 +1909,7 @@ add_clp_to_name_tree(struct nfs4_client *new_clp, struct rb_root *root)
 static struct nfs4_client *
 find_clp_in_name_tree(struct xdr_netobj *name, struct rb_root *root)
 {
-       long long cmp;
+       int cmp;
        struct rb_node *node = root->rb_node;
        struct nfs4_client *clp;
 
@@ -3057,10 +3059,9 @@ static struct nfs4_file *nfsd4_alloc_file(void)
 }
 
 /* OPEN Share state helper functions */
-static void nfsd4_init_file(struct nfs4_file *fp, struct knfsd_fh *fh)
+static void nfsd4_init_file(struct knfsd_fh *fh, unsigned int hashval,
+                               struct nfs4_file *fp)
 {
-       unsigned int hashval = file_hashval(fh);
-
        lockdep_assert_held(&state_lock);
 
        atomic_set(&fp->fi_ref, 1);
@@ -3073,7 +3074,7 @@ static void nfsd4_init_file(struct nfs4_file *fp, struct knfsd_fh *fh)
        fp->fi_share_deny = 0;
        memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
        memset(fp->fi_access, 0, sizeof(fp->fi_access));
-       hlist_add_head(&fp->fi_hash, &file_hashtbl[hashval]);
+       hlist_add_head_rcu(&fp->fi_hash, &file_hashtbl[hashval]);
 }
 
 void
@@ -3294,17 +3295,14 @@ move_to_close_lru(struct nfs4_ol_stateid *s, struct net *net)
 
 /* search file_hashtbl[] for file */
 static struct nfs4_file *
-find_file_locked(struct knfsd_fh *fh)
+find_file_locked(struct knfsd_fh *fh, unsigned int hashval)
 {
-       unsigned int hashval = file_hashval(fh);
        struct nfs4_file *fp;
 
-       lockdep_assert_held(&state_lock);
-
-       hlist_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) {
+       hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash) {
                if (nfsd_fh_match(&fp->fi_fhandle, fh)) {
-                       get_nfs4_file(fp);
-                       return fp;
+                       if (atomic_inc_not_zero(&fp->fi_ref))
+                               return fp;
                }
        }
        return NULL;
@@ -3314,10 +3312,11 @@ static struct nfs4_file *
 find_file(struct knfsd_fh *fh)
 {
        struct nfs4_file *fp;
+       unsigned int hashval = file_hashval(fh);
 
-       spin_lock(&state_lock);
-       fp = find_file_locked(fh);
-       spin_unlock(&state_lock);
+       rcu_read_lock();
+       fp = find_file_locked(fh, hashval);
+       rcu_read_unlock();
        return fp;
 }
 
@@ -3325,11 +3324,18 @@ static struct nfs4_file *
 find_or_add_file(struct nfs4_file *new, struct knfsd_fh *fh)
 {
        struct nfs4_file *fp;
+       unsigned int hashval = file_hashval(fh);
+
+       rcu_read_lock();
+       fp = find_file_locked(fh, hashval);
+       rcu_read_unlock();
+       if (fp)
+               return fp;
 
        spin_lock(&state_lock);
-       fp = find_file_locked(fh);
-       if (fp == NULL) {
-               nfsd4_init_file(new, fh);
+       fp = find_file_locked(fh, hashval);
+       if (likely(fp == NULL)) {
+               nfsd4_init_file(fh, hashval, new);
                fp = new;
        }
        spin_unlock(&state_lock);
@@ -4127,7 +4133,7 @@ void nfsd4_cleanup_open_state(struct nfsd4_compound_state *cstate,
                nfs4_put_stateowner(so);
        }
        if (open->op_file)
-               nfsd4_free_file(open->op_file);
+               kmem_cache_free(file_slab, open->op_file);
        if (open->op_stp)
                nfs4_put_stid(&open->op_stp->st_stid);
 }