Commit 9ceddd9d authored by Trond Myklebust's avatar Trond Myklebust Committed by J. Bruce Fields
Browse files

knfsd: Allow lockless lookups of the exports 



Convert structs svc_expkey and svc_export to allow RCU protected lookups.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent fd5d2f78

fs/nfsd/export.c

+7 −7
Original line number Diff line number Diff line
@@ -46,7 +46,7 @@ static void expkey_put(struct kref *ref) 
	    !test_bit(CACHE_NEGATIVE, &key->h.flags))

		path_put(&key->ek_path);

	auth_domain_put(key->ek_client);

	kfree(key);

	kfree_rcu(key, ek_rcu);

}



static void expkey_request(struct cache_detail *cd,
@@ -265,7 +265,7 @@ svc_expkey_lookup(struct cache_detail *cd, struct svc_expkey *item) 
	struct cache_head *ch;

	int hash = svc_expkey_hash(item);



	ch = sunrpc_cache_lookup(cd, &item->h, hash);

	ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);

	if (ch)

		return container_of(ch, struct svc_expkey, h);

	else
@@ -314,7 +314,7 @@ static void svc_export_put(struct kref *ref) 
	auth_domain_put(exp->ex_client);

	nfsd4_fslocs_free(&exp->ex_fslocs);

	kfree(exp->ex_uuid);

	kfree(exp);

	kfree_rcu(exp, ex_rcu);

}



static void svc_export_request(struct cache_detail *cd,
@@ -780,7 +780,7 @@ svc_export_lookup(struct svc_export *exp) 
	struct cache_head *ch;

	int hash = svc_export_hash(exp);



	ch = sunrpc_cache_lookup(exp->cd, &exp->h, hash);

	ch = sunrpc_cache_lookup_rcu(exp->cd, &exp->h, hash);

	if (ch)

		return container_of(ch, struct svc_export, h);

	else
@@ -1216,9 +1216,9 @@ static int e_show(struct seq_file *m, void *p) 
}



const struct seq_operations nfs_exports_op = {

	.start	= cache_seq_start,

	.next	= cache_seq_next,

	.stop	= cache_seq_stop,

	.start	= cache_seq_start_rcu,

	.next	= cache_seq_next_rcu,

	.stop	= cache_seq_stop_rcu,

	.show	= e_show,

};

fs/nfsd/export.h

+2 −0
Original line number Diff line number Diff line
@@ -61,6 +61,7 @@ struct svc_export { 
	u32			ex_layout_types;

	struct nfsd4_deviceid_map *ex_devid_map;

	struct cache_detail	*cd;

	struct rcu_head		ex_rcu;

};



/* an "export key" (expkey) maps a filehandlefragement to an
@@ -75,6 +76,7 @@ struct svc_expkey { 
	u32			ek_fsid[6];



	struct path		ek_path;

	struct rcu_head		ek_rcu;

};



#define EX_ISSYNC(exp)		(!((exp)->ex_flags & NFSEXP_ASYNC))