Commit 3c9e502b authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Add a helper nfs_client_for_each_server() 



Add a helper nfs_client_for_each_server() to iterate through all the
filesystems that are attached to a struct nfs_client, and apply
a function to all the active ones.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent 58ac3e59

fs/nfs/internal.h

+3 −1
Original line number Diff line number Diff line
@@ -417,7 +417,9 @@ extern int __init register_nfs_fs(void); 
extern void __exit unregister_nfs_fs(void);

extern bool nfs_sb_active(struct super_block *sb);

extern void nfs_sb_deactive(struct super_block *sb);



extern int nfs_client_for_each_server(struct nfs_client *clp,

				      int (*fn)(struct nfs_server *, void *),

				      void *data);

/* io.c */

extern void nfs_start_io_read(struct inode *inode);

extern void nfs_end_io_read(struct inode *inode);

fs/nfs/super.c

+35 −0
Original line number Diff line number Diff line
@@ -176,6 +176,41 @@ void nfs_sb_deactive(struct super_block *sb) 
}

EXPORT_SYMBOL_GPL(nfs_sb_deactive);



static int __nfs_list_for_each_server(struct list_head *head,

		int (*fn)(struct nfs_server *, void *),

		void *data)

{

	struct nfs_server *server, *last = NULL;

	int ret = 0;



	rcu_read_lock();

	list_for_each_entry_rcu(server, head, client_link) {

		if (!nfs_sb_active(server->super))

			continue;

		rcu_read_unlock();

		if (last)

			nfs_sb_deactive(last->super);

		last = server;

		ret = fn(server, data);

		if (ret)

			goto out;

		rcu_read_lock();

	}

	rcu_read_unlock();

out:

	if (last)

		nfs_sb_deactive(last->super);

	return ret;

}



int nfs_client_for_each_server(struct nfs_client *clp,

		int (*fn)(struct nfs_server *, void *),

		void *data)

{

	return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data);

}

EXPORT_SYMBOL_GPL(nfs_client_for_each_server);



/*

 * Deliver file system statistics to userspace

 */