X-Git-Url: http://git.onelab.eu/?p=linux-2.6.git;a=blobdiff_plain;f=lib%2Fidr.c;fp=lib%2Fidr.c;h=de19030a999bada012fc63c2ed53a1b3807eb245;hp=81fc430602ee8f4c2b4e336a606813ad54b0e5b2;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hpb=cee37fe97739d85991964371c1f3a745c00dd236

diff --git a/lib/idr.c b/lib/idr.c
index 81fc43060..de19030a9 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -6,20 +6,20 @@
  * Modified by George Anzinger to reuse immediately and to use
  * find bit instructions.  Also removed _irq on spinlocks.
  *
- * Small id to pointer translation service.  
+ * Small id to pointer translation service.
  *
- * It uses a radix tree like structure as a sparse array indexed 
+ * It uses a radix tree like structure as a sparse array indexed
  * by the id to obtain the pointer.  The bitmap makes allocating
- * a new id quick.  
+ * a new id quick.
  *
  * You call it to allocate an id (an int) an associate with that id a
  * pointer or what ever, we treat it as a (void *).  You can pass this
  * id to a user for him to pass back at a later time.  You then pass
  * that id to this code and it returns your pointer.
 
- * You can release ids at any time. When all ids are released, most of 
+ * You can release ids at any time. When all ids are released, most of
  * the memory is returned (we keep IDR_FREE_MAX) in a local pool so we
- * don't need to go to the memory "store" during an id allocate, just 
+ * don't need to go to the memory "store" during an id allocate, just
  * so you don't need to be too concerned about locking and conflicts
  * with the slab allocator.
  */
@@ -48,15 +48,21 @@ static struct idr_layer *alloc_layer(struct idr *idp)
 	return(p);
 }
 
+/* only called when idp->lock is held */
+static void __free_layer(struct idr *idp, struct idr_layer *p)
+{
+	p->ary[0] = idp->id_free;
+	idp->id_free = p;
+	idp->id_free_cnt++;
+}
+
 static void free_layer(struct idr *idp, struct idr_layer *p)
 {
 	/*
 	 * Depends on the return element being zeroed.
 	 */
 	spin_lock(&idp->lock);
-	p->ary[0] = idp->id_free;
-	idp->id_free = p;
-	idp->id_free_cnt++;
+	__free_layer(idp, p);
 	spin_unlock(&idp->lock);
 }
 
@@ -72,12 +78,12 @@ static void free_layer(struct idr *idp, struct idr_layer *p)
  * If the system is REALLY out of memory this function returns 0,
  * otherwise 1.
  */
-int idr_pre_get(struct idr *idp, unsigned gfp_mask)
+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);
-		if(new == NULL)
+		if (new == NULL)
 			return (0);
 		free_layer(idp, new);
 	}
@@ -107,7 +113,7 @@ static int sub_alloc(struct idr *idp, void *ptr, int *starting_id)
 		if (m == IDR_SIZE) {
 			/* no space available go back to previous layer. */
 			l++;
-			id = (id | ((1 << (IDR_BITS*l))-1)) + 1;
+			id = (id | ((1 << (IDR_BITS * l)) - 1)) + 1;
 			if (!(p = pa[l])) {
 				*starting_id = id;
 				return -2;
@@ -161,7 +167,7 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
 {
 	struct idr_layer *p, *new;
 	int layers, v, id;
-	
+
 	id = starting_id;
 build_up:
 	p = idp->top;
@@ -175,7 +181,7 @@ build_up:
 	 * Add a new layer to the top of the tree if the requested
 	 * id is larger than the currently allocated space.
 	 */
-	while ((layers < MAX_LEVEL) && (id >= (1 << (layers*IDR_BITS)))) {
+	while ((layers < (MAX_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) {
 		layers++;
 		if (!p->count)
 			continue;
@@ -184,12 +190,14 @@ build_up:
 			 * The allocation failed.  If we built part of
 			 * the structure tear it down.
 			 */
+			spin_lock(&idp->lock);
 			for (new = p; p && p != idp->top; new = p) {
 				p = p->ary[0];
 				new->ary[0] = NULL;
 				new->bitmap = new->count = 0;
-				free_layer(idp, new);
+				__free_layer(idp, new);
 			}
+			spin_unlock(&idp->lock);
 			return -1;
 		}
 		new->ary[0] = p;
@@ -207,7 +215,7 @@ build_up:
 }
 
 /**
- * idr_get_new_above - allocate new idr entry above a start 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
  * @start_id: id to start search at
@@ -225,6 +233,7 @@ build_up:
 int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
 {
 	int rv;
+
 	rv = idr_get_new_above_int(idp, ptr, starting_id);
 	/*
 	 * This is a cheap hack until the IDR code can be fixed to
@@ -259,6 +268,7 @@ EXPORT_SYMBOL(idr_get_new_above);
 int idr_get_new(struct idr *idp, void *ptr, int *id)
 {
 	int rv;
+
 	rv = idr_get_new_above_int(idp, ptr, 0);
 	/*
 	 * This is a cheap hack until the IDR code can be fixed to
@@ -306,11 +316,10 @@ static void sub_remove(struct idr *idp, int shift, int id)
 			free_layer(idp, **paa);
 			**paa-- = NULL;
 		}
-		if ( ! *paa )
+		if (!*paa)
 			idp->layers = 0;
-	} else {
+	} else
 		idr_remove_warning(id);
-	}
 }
 
 /**
@@ -326,9 +335,8 @@ void idr_remove(struct idr *idp, int id)
 	id &= MAX_ID_MASK;
 
 	sub_remove(idp, (idp->layers - 1) * IDR_BITS, id);
-	if ( idp->top && idp->top->count == 1 && 
-	     (idp->layers > 1) &&
-	     idp->top->ary[0]){  // We can drop a layer
+	if (idp->top && idp->top->count == 1 && (idp->layers > 1) &&
+	    idp->top->ary[0]) {  // We can drop a layer
 
 		p = idp->top->ary[0];
 		idp->top->bitmap = idp->top->count = 0;
@@ -337,7 +345,6 @@ void idr_remove(struct idr *idp, int id)
 		--idp->layers;
 	}
 	while (idp->id_free_cnt >= IDR_FREE_MAX) {
-		
 		p = alloc_layer(idp);
 		kmem_cache_free(idr_layer_cache, p);
 		return;
@@ -345,6 +352,19 @@ void idr_remove(struct idr *idp, int id)
 }
 EXPORT_SYMBOL(idr_remove);
 
+/**
+ * idr_destroy - release all cached layers within an idr tree
+ * idp: idr handle
+ */
+void idr_destroy(struct idr *idp)
+{
+	while (idp->id_free_cnt) {
+		struct idr_layer *p = alloc_layer(idp);
+		kmem_cache_free(idr_layer_cache, p);
+	}
+}
+EXPORT_SYMBOL(idr_destroy);
+
 /**
  * idr_find - return pointer for given id
  * @idp: idr handle
@@ -378,8 +398,8 @@ void *idr_find(struct idr *idp, int id)
 }
 EXPORT_SYMBOL(idr_find);
 
-static void idr_cache_ctor(void * idr_layer, 
-			   kmem_cache_t *idr_layer_cache, unsigned long flags)
+static void idr_cache_ctor(void * idr_layer, kmem_cache_t *idr_layer_cache,
+		unsigned long flags)
 {
 	memset(idr_layer, 0, sizeof(struct idr_layer));
 }
@@ -387,7 +407,7 @@ static void idr_cache_ctor(void * idr_layer,
 static  int init_id_cache(void)
 {
 	if (!idr_layer_cache)
-		idr_layer_cache = kmem_cache_create("idr_layer_cache", 
+		idr_layer_cache = kmem_cache_create("idr_layer_cache",
 			sizeof(struct idr_layer), 0, 0, idr_cache_ctor, NULL);
 	return 0;
 }