Commit ef818a28 authored by Steve Dickson's avatar Steve Dickson Committed by Trond Myklebust
Browse files

NFS: Stop sillyname renames and unmounts from racing 



Added an active/deactive mechanism to the nfs_server structure
allowing async operations to hold off umount until the
operations are done.

Signed-off-by: default avatarSteve Dickson <steved@redhat.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 2f74c0a0

fs/nfs/client.c

+3 −0
Original line number Diff line number Diff line
@@ -729,6 +729,9 @@ static struct nfs_server *nfs_alloc_server(void) 
	INIT_LIST_HEAD(&server->client_link);

	INIT_LIST_HEAD(&server->master_link);



	init_waitqueue_head(&server->active_wq);

	atomic_set(&server->active, 0);



	server->io_stats = nfs_alloc_iostats();

	if (!server->io_stats) {

		kfree(server);

fs/nfs/internal.h

+2 −0
Original line number Diff line number Diff line
@@ -160,6 +160,8 @@ extern struct rpc_stat nfs_rpcstat; 


extern int __init register_nfs_fs(void);

extern void __exit unregister_nfs_fs(void);

extern void nfs_sb_active(struct nfs_server *server);

extern void nfs_sb_deactive(struct nfs_server *server);



/* namespace.c */

extern char *nfs_path(const char *base,

fs/nfs/super.c

+24 −0
Original line number Diff line number Diff line
@@ -202,6 +202,7 @@ static int nfs_get_sb(struct file_system_type *, int, const char *, void *, stru 
static int nfs_xdev_get_sb(struct file_system_type *fs_type,

		int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);

static void nfs_kill_super(struct super_block *);

static void nfs_put_super(struct super_block *);



static struct file_system_type nfs_fs_type = {

	.owner		= THIS_MODULE,
@@ -223,6 +224,7 @@ static const struct super_operations nfs_sops = { 
	.alloc_inode	= nfs_alloc_inode,

	.destroy_inode	= nfs_destroy_inode,

	.write_inode	= nfs_write_inode,

	.put_super	= nfs_put_super,

	.statfs		= nfs_statfs,

	.clear_inode	= nfs_clear_inode,

	.umount_begin	= nfs_umount_begin,
@@ -325,6 +327,28 @@ void __exit unregister_nfs_fs(void) 
	unregister_filesystem(&nfs_fs_type);

}



void nfs_sb_active(struct nfs_server *server)

{

	atomic_inc(&server->active);

}



void nfs_sb_deactive(struct nfs_server *server)

{

	if (atomic_dec_and_test(&server->active))

		wake_up(&server->active_wq);

}



static void nfs_put_super(struct super_block *sb)

{

	struct nfs_server *server = NFS_SB(sb);

	/*

	 * Make sure there are no outstanding ops to this server.

	 * If so, wait for them to finish before allowing the

	 * unmount to continue.

	 */

	wait_event(server->active_wq, atomic_read(&server->active) == 0);

}



/*

 * Deliver file system statistics to userspace

 */

fs/nfs/unlink.c

+4 −0
Original line number Diff line number Diff line
@@ -14,6 +14,8 @@ 
#include <linux/sched.h>

#include <linux/wait.h>



#include "internal.h"



struct nfs_unlinkdata {

	struct hlist_node list;

	struct nfs_removeargs args;
@@ -113,6 +115,7 @@ static void nfs_async_unlink_release(void *calldata) 
	struct nfs_unlinkdata	*data = calldata;



	nfs_dec_sillycount(data->dir);

	nfs_sb_deactive(NFS_SERVER(data->dir));

	nfs_free_unlinkdata(data);

}
@@ -153,6 +156,7 @@ static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct n 
		nfs_dec_sillycount(dir);

		return 0;

	}

	nfs_sb_active(NFS_SERVER(dir));

	data->args.fh = NFS_FH(dir);

	nfs_fattr_init(&data->res.dir_attr);

include/linux/nfs_fs_sb.h

+6 −0
Original line number Diff line number Diff line
@@ -3,6 +3,9 @@ 


#include <linux/list.h>

#include <linux/backing-dev.h>

#include <linux/wait.h>



#include <asm/atomic.h>



struct nfs_iostats;
@@ -110,6 +113,9 @@ struct nfs_server { 
						   filesystem */

#endif

	void (*destroy)(struct nfs_server *);



	atomic_t active; /* Keep trace of any activity to this server */

	wait_queue_head_t active_wq;  /* Wait for any activity to stop  */

};



/* Server capabilities */