Commit 2e32cf5e authored by Al Viro's avatar Al Viro
Browse files

cifs: rcu-delay unload_nls() and freeing sbi 



makes ->d_hash(), ->d_compare() and ->permission() safety in RCU mode
independent from vfsmount_lock.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent baa40671

fs/cifs/cifs_fs_sb.h

+1 −0
Original line number Diff line number Diff line
@@ -65,5 +65,6 @@ struct cifs_sb_info { 
	char   *mountdata; /* options received at mount time or via DFS refs */

	struct backing_dev_info bdi;

	struct delayed_work prune_tlinks;

	struct rcu_head rcu;

};

#endif				/* _CIFS_FS_SB_H */

fs/cifs/connect.c

+8 −2
Original line number Diff line number Diff line
@@ -3755,6 +3755,13 @@ CIFSTCon(const unsigned int xid, struct cifs_ses *ses, 
	return rc;

}



static void delayed_free(struct rcu_head *p)

{

	struct cifs_sb_info *sbi = container_of(p, struct cifs_sb_info, rcu);

	unload_nls(sbi->local_nls);

	kfree(sbi);

}



void

cifs_umount(struct cifs_sb_info *cifs_sb)

{
@@ -3779,8 +3786,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb) 


	bdi_destroy(&cifs_sb->bdi);

	kfree(cifs_sb->mountdata);

	unload_nls(cifs_sb->local_nls);

	kfree(cifs_sb);

	call_rcu(&cifs_sb->rcu, delayed_free);

}



int