X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fafs%2Fcell.c;h=5e1df14e16b188d9a47501a28c48ce65a4be4c5b;hb=03fc922f4085a0139f313831fe2dc6fed467cd2d;hp=970d38f305652f3b472fe558ffb68bb4376c283f;hpb=fe2520094d88018423dfc42b3cd0015f74e8adea;p=linux-2.6

diff --git a/fs/afs/cell.c b/fs/afs/cell.c
index 970d38f305..5e1df14e16 100644
--- a/fs/afs/cell.c
+++ b/fs/afs/cell.c
@@ -20,7 +20,7 @@
 DECLARE_RWSEM(afs_proc_cells_sem);
 LIST_HEAD(afs_proc_cells);
 
-static struct list_head afs_cells = LIST_HEAD_INIT(afs_cells);
+static LIST_HEAD(afs_cells);
 static DEFINE_RWLOCK(afs_cells_lock);
 static DECLARE_RWSEM(afs_cells_sem); /* add/remove serialisation */
 static DECLARE_WAIT_QUEUE_HEAD(afs_cells_freeable_wq);
@@ -127,14 +127,21 @@ struct afs_cell *afs_cell_create(const char *name, char *vllist)
 
 	_enter("%s,%s", name, vllist);
 
+	down_write(&afs_cells_sem);
+	read_lock(&afs_cells_lock);
+	list_for_each_entry(cell, &afs_cells, link) {
+		if (strcasecmp(cell->name, name) == 0)
+			goto duplicate_name;
+	}
+	read_unlock(&afs_cells_lock);
+
 	cell = afs_cell_alloc(name, vllist);
 	if (IS_ERR(cell)) {
 		_leave(" = %ld", PTR_ERR(cell));
+		up_write(&afs_cells_sem);
 		return cell;
 	}
 
-	down_write(&afs_cells_sem);
-
 	/* add a proc directory for this cell */
 	ret = afs_proc_cell_setup(cell);
 	if (ret < 0)
@@ -167,6 +174,11 @@ error:
 	kfree(cell);
 	_leave(" = %d", ret);
 	return ERR_PTR(ret);
+
+duplicate_name:
+	read_unlock(&afs_cells_lock);
+	up_write(&afs_cells_sem);
+	return ERR_PTR(-EEXIST);
 }
 
 /*