X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=lib%2Fidr.c;h=1cac726c44bc17cc6fa1a7b5ab6358279a0c9a5d;hb=f01eb3640308c005d31b29d0a8bc2b7acb4e3f75;hp=7a785a0c2ea0fccead72653a0fd66af5111888ea;hpb=6ff2d39b91aec3dcae951afa982059e3dd9b49dc;p=safe%2Fjmp%2Flinux-2.6

diff --git a/lib/idr.c b/lib/idr.c
index 7a785a0..1cac726 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -121,7 +121,7 @@ int idr_pre_get(struct idr *idp, gfp_t gfp_mask)
 {
 	while (idp->id_free_cnt < IDR_FREE_MAX) {
 		struct idr_layer *new;
-		new = kmem_cache_alloc(idr_layer_cache, gfp_mask);
+		new = kmem_cache_zalloc(idr_layer_cache, gfp_mask);
 		if (new == NULL)
 			return (0);
 		move_to_free_list(idp, new);
@@ -220,8 +220,14 @@ build_up:
 	 */
 	while ((layers < (MAX_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) {
 		layers++;
-		if (!p->count)
+		if (!p->count) {
+			/* special case: if the tree is currently empty,
+			 * then we grow the tree by moving the top node
+			 * upwards.
+			 */
+			p->layer++;
 			continue;
+		}
 		if (!(new = get_from_free_list(idp))) {
 			/*
 			 * The allocation failed.  If we built part of
@@ -275,7 +281,7 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
 /**
  * idr_get_new_above - allocate new idr entry above or equal to a start id
  * @idp: idr handle
- * @ptr: pointer you want associated with the ide
+ * @ptr: pointer you want associated with the id
  * @start_id: id to start search at
  * @id: pointer to the allocated handle
  *
@@ -286,7 +292,7 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
  * and go back to the idr_pre_get() call.  If the idr is full, it will
  * return -ENOSPC.
  *
- * @id returns a value in the range 0 ... 0x7fffffff
+ * @id returns a value in the range @starting_id ... 0x7fffffff
  */
 int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
 {
@@ -307,7 +313,7 @@ EXPORT_SYMBOL(idr_get_new_above);
 /**
  * idr_get_new - allocate new idr entry
  * @idp: idr handle
- * @ptr: pointer you want associated with the ide
+ * @ptr: pointer you want associated with the id
  * @id: pointer to the allocated handle
  *
  * This is the allocate id function.  It should be called with any
@@ -443,6 +449,7 @@ void idr_remove_all(struct idr *idp)
 
 	n = idp->layers * IDR_BITS;
 	p = idp->top;
+	rcu_assign_pointer(idp->top, NULL);
 	max = 1 << n;
 
 	id = 0;
@@ -461,7 +468,6 @@ void idr_remove_all(struct idr *idp)
 			p = *--paa;
 		}
 	}
-	rcu_assign_pointer(idp->top, NULL);
 	idp->layers = 0;
 }
 EXPORT_SYMBOL(idr_remove_all);
@@ -573,6 +579,52 @@ int idr_for_each(struct idr *idp,
 EXPORT_SYMBOL(idr_for_each);
 
 /**
+ * idr_get_next - lookup next object of id to given id.
+ * @idp: idr handle
+ * @id:  pointer to lookup key
+ *
+ * Returns pointer to registered object with id, which is next number to
+ * given id.
+ */
+
+void *idr_get_next(struct idr *idp, int *nextidp)
+{
+	struct idr_layer *p, *pa[MAX_LEVEL];
+	struct idr_layer **paa = &pa[0];
+	int id = *nextidp;
+	int n, max;
+
+	/* find first ent */
+	n = idp->layers * IDR_BITS;
+	max = 1 << n;
+	p = rcu_dereference(idp->top);
+	if (!p)
+		return NULL;
+
+	while (id < max) {
+		while (n > 0 && p) {
+			n -= IDR_BITS;
+			*paa++ = p;
+			p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
+		}
+
+		if (p) {
+			*nextidp = id;
+			return p;
+		}
+
+		id += 1 << n;
+		while (n < fls(id)) {
+			n += IDR_BITS;
+			p = *--paa;
+		}
+	}
+	return NULL;
+}
+
+
+
+/**
  * idr_replace - replace pointer for given id
  * @idp: idr handle
  * @ptr: pointer you want associated with the id
@@ -617,16 +669,10 @@ void *idr_replace(struct idr *idp, void *ptr, int id)
 }
 EXPORT_SYMBOL(idr_replace);
 
-static void idr_cache_ctor(void *idr_layer)
-{
-	memset(idr_layer, 0, sizeof(struct idr_layer));
-}
-
 void __init idr_init_cache(void)
 {
 	idr_layer_cache = kmem_cache_create("idr_layer_cache",
-				sizeof(struct idr_layer), 0, SLAB_PANIC,
-				idr_cache_ctor);
+				sizeof(struct idr_layer), 0, SLAB_PANIC, NULL);
 }
 
 /**
@@ -717,7 +763,7 @@ EXPORT_SYMBOL(ida_pre_get);
  * and go back to the ida_pre_get() call.  If the ida is full, it will
  * return -ENOSPC.
  *
- * @p_id returns a value in the range 0 ... 0x7fffffff.
+ * @p_id returns a value in the range @starting_id ... 0x7fffffff.
  */
 int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
 {