From 298fc3558b9c1f5324c5ec6d5c587ca9ae6cc826 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 27 Aug 2013 16:27:04 -0400 Subject: [PATCH] SUNRPC: Add a helper to allow sharing of rpc_pipefs directory objects Add support for looking up existing objects and creating new ones if there is no match. Signed-off-by: Trond Myklebust --- include/linux/sunrpc/rpc_pipe_fs.h | 6 +++++ net/sunrpc/rpc_pipe.c | 35 ++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+) diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h index b0cf1812be72..a353e0300b54 100644 --- a/include/linux/sunrpc/rpc_pipe_fs.h +++ b/include/linux/sunrpc/rpc_pipe_fs.h @@ -106,6 +106,12 @@ extern int rpc_add_pipe_dir_object(struct net *net, extern void rpc_remove_pipe_dir_object(struct net *net, struct rpc_pipe_dir_head *pdh, struct rpc_pipe_dir_object *pdo); +extern struct rpc_pipe_dir_object *rpc_find_or_alloc_pipe_dir_object( + struct net *net, + struct rpc_pipe_dir_head *pdh, + int (*match)(struct rpc_pipe_dir_object *, void *), + struct rpc_pipe_dir_object *(*alloc)(void *), + void *data); struct cache_detail; extern struct dentry *rpc_create_cache_dir(struct dentry *, diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c index a35b2f402aaa..f94567b45bb3 100644 --- a/net/sunrpc/rpc_pipe.c +++ b/net/sunrpc/rpc_pipe.c @@ -982,6 +982,41 @@ rpc_remove_pipe_dir_object(struct net *net, } EXPORT_SYMBOL_GPL(rpc_remove_pipe_dir_object); +/** + * rpc_find_or_alloc_pipe_dir_object + * @net: pointer to struct net + * @pdh: pointer to struct rpc_pipe_dir_head + * @match: match struct rpc_pipe_dir_object to data + * @alloc: allocate a new struct rpc_pipe_dir_object + * @data: user defined data for match() and alloc() + * + */ +struct rpc_pipe_dir_object * +rpc_find_or_alloc_pipe_dir_object(struct net *net, + struct rpc_pipe_dir_head *pdh, + int (*match)(struct rpc_pipe_dir_object *, void *), + struct rpc_pipe_dir_object *(*alloc)(void *), + void *data) +{ + struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); + struct rpc_pipe_dir_object *pdo; + + mutex_lock(&sn->pipefs_sb_lock); + list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) { + if (!match(pdo, data)) + continue; + goto out; + } + pdo = alloc(data); + if (!pdo) + goto out; + rpc_add_pipe_dir_object_locked(net, pdh, pdo); +out: + mutex_unlock(&sn->pipefs_sb_lock); + return pdo; +} +EXPORT_SYMBOL_GPL(rpc_find_or_alloc_pipe_dir_object); + static void rpc_create_pipe_dir_objects(struct rpc_pipe_dir_head *pdh) { -- 2.30.2