patch-2.1.36 linux/net/core/skbuff.c

• Lines: 692
• Date: Tue Apr 22 22:46:27 1997
• Orig file: v2.1.35/linux/net/core/skbuff.c
• Orig date: Mon Apr 14 16:28:27 1997

diff -u --recursive --new-file v2.1.35/linux/net/core/skbuff.c linux/net/core/skbuff.c
@@ -60,9 +60,9 @@
  *	Resource tracking variables
  */
 
-static atomic_t net_skbcount = ATOMIC_INIT;
-static atomic_t net_allocs = ATOMIC_INIT;
-static atomic_t net_fails  = ATOMIC_INIT;
+static atomic_t net_skbcount = ATOMIC_INIT(0);
+static atomic_t net_allocs = ATOMIC_INIT(0);
+static atomic_t net_fails  = ATOMIC_INIT(0);
 
 extern atomic_t ip_frag_mem;
 
@@ -87,509 +87,17 @@
 #endif	
 }
 
-#if CONFIG_SKB_CHECK
-
-/*
- *	Debugging paranoia. Used for debugging network stacks.
- */
-
-int skb_check(struct sk_buff *skb, int head, int line, char *file)
-{
-	if (head) {
-		if (skb->magic_debug_cookie != SK_HEAD_SKB) {
-			printk("File: %s Line %d, found a bad skb-head\n",
-				file,line);
-			return -1;
-		}
-		if (!skb->next || !skb->prev) {
-			printk("skb_check: head without next or prev\n");
-			return -1;
-		}
-		if (skb->next->magic_debug_cookie != SK_HEAD_SKB
-			&& skb->next->magic_debug_cookie != SK_GOOD_SKB) {
-			printk("File: %s Line %d, bad next head-skb member\n",
-				file,line);
-			return -1;
-		}
-		if (skb->prev->magic_debug_cookie != SK_HEAD_SKB
-			&& skb->prev->magic_debug_cookie != SK_GOOD_SKB) {
-			printk("File: %s Line %d, bad prev head-skb member\n",
-				file,line);
-			return -1;
-		}
-		return 0;
-	}
-	if (skb->next != NULL && skb->next->magic_debug_cookie != SK_HEAD_SKB
-		&& skb->next->magic_debug_cookie != SK_GOOD_SKB) {
-		printk("File: %s Line %d, bad next skb member\n",
-			file,line);
-		return -1;
-	}
-	if (skb->prev != NULL && skb->prev->magic_debug_cookie != SK_HEAD_SKB
-		&& skb->prev->magic_debug_cookie != SK_GOOD_SKB) {
-		printk("File: %s Line %d, bad prev skb member\n",
-			file,line);
-		return -1;
-	}
-
-
-	if(skb->magic_debug_cookie==SK_FREED_SKB)
-	{
-		printk("File: %s Line %d, found a freed skb lurking in the undergrowth!\n",
-			file,line);
-		printk("skb=%p, real size=%d, free=%d\n",
-			skb,skb->truesize,skb->free);
-		return -1;
-	}
-	if(skb->magic_debug_cookie!=SK_GOOD_SKB)
-	{
-		printk("File: %s Line %d, passed a non skb!\n", file,line);
-		printk("skb=%p, real size=%d, free=%d\n",
-			skb,skb->truesize,skb->free);
-		return -1;
-	}
-	if(skb->head>skb->data)
-	{
-		printk("File: %s Line %d, head > data !\n", file,line);
-		printk("skb=%p, head=%p, data=%p\n",
-			skb,skb->head,skb->data);
-		return -1;
-	}
-	if(skb->tail>skb->end)
-	{
-		printk("File: %s Line %d, tail > end!\n", file,line);
-		printk("skb=%p, tail=%p, end=%p\n",
-			skb,skb->tail,skb->end);
-		return -1;
-	}
-	if(skb->data>skb->tail)
-	{
-		printk("File: %s Line %d, data > tail!\n", file,line);
-		printk("skb=%p, data=%p, tail=%p\n",
-			skb,skb->data,skb->tail);
-		return -1;
-	}
-	if(skb->tail-skb->data!=skb->len)
-	{
-		printk("File: %s Line %d, wrong length\n", file,line);
-		printk("skb=%p, data=%p, end=%p len=%ld\n",
-			skb,skb->data,skb->end,skb->len);
-		return -1;
-	}
-	if((unsigned long) skb->end > (unsigned long) skb)
-	{
-		printk("File: %s Line %d, control overrun\n", file,line);
-		printk("skb=%p, end=%p\n",
-			skb,skb->end);
-		return -1;
-	}
-
-	/* Guess it might be acceptable then */
-	return 0;
-}
-#endif
-
-
-#if CONFIG_SKB_CHECK
-void skb_queue_head_init(struct sk_buff_head *list)
-{
-	list->prev = (struct sk_buff *)list;
-	list->next = (struct sk_buff *)list;
-	list->qlen = 0;
-	list->magic_debug_cookie = SK_HEAD_SKB;
-}
-
-
-/*
- *	Insert an sk_buff at the start of a list.
- */
-void skb_queue_head(struct sk_buff_head *list_,struct sk_buff *newsk)
-{
-	unsigned long flags;
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-	save_flags(flags);
-	cli();
-
-	IS_SKB(newsk);
-	IS_SKB_HEAD(list);
-	if (newsk->next || newsk->prev)
-		printk("Suspicious queue head: sk_buff on list!\n");
-
-	newsk->next = list->next;
-	newsk->prev = list;
-
-	newsk->next->prev = newsk;
-	newsk->prev->next = newsk;
-	newsk->list = list_;
-	list_->qlen++;
-
-	restore_flags(flags);
-}
-
-void __skb_queue_head(struct sk_buff_head *list_,struct sk_buff *newsk)
-{
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-
-	IS_SKB(newsk);
-	IS_SKB_HEAD(list);
-	if (newsk->next || newsk->prev)
-		printk("Suspicious queue head: sk_buff on list!\n");
-
-	newsk->next = list->next;
-	newsk->prev = list;
-
-	newsk->next->prev = newsk;
-	newsk->prev->next = newsk;
-	newsk->list = list_;
-	list_->qlen++;
-
-}
-
-/*
- *	Insert an sk_buff at the end of a list.
- */
-void skb_queue_tail(struct sk_buff_head *list_, struct sk_buff *newsk)
-{
-	unsigned long flags;
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-	save_flags(flags);
-	cli();
-
-	if (newsk->next || newsk->prev)
-		printk("Suspicious queue tail: sk_buff on list!\n");
-	IS_SKB(newsk);
-	IS_SKB_HEAD(list);
-
-	newsk->next = list;
-	newsk->prev = list->prev;
-
-	newsk->next->prev = newsk;
-	newsk->prev->next = newsk;
-	
-	newsk->list = list_;
-	list_->qlen++;
-
-	restore_flags(flags);
-}
-
-void __skb_queue_tail(struct sk_buff_head *list_, struct sk_buff *newsk)
-{
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-	if (newsk->next || newsk->prev)
-		printk("Suspicious queue tail: sk_buff on list!\n");
-	IS_SKB(newsk);
-	IS_SKB_HEAD(list);
-
-	newsk->next = list;
-	newsk->prev = list->prev;
-
-	newsk->next->prev = newsk;
-	newsk->prev->next = newsk;
-	
-	newsk->list = list_;
-	list_->qlen++;
-}
-
-/*
- *	Remove an sk_buff from a list. This routine is also interrupt safe
- *	so you can grab read and free buffers as another process adds them.
- */
-
-struct sk_buff *skb_dequeue(struct sk_buff_head *list_)
-{
-	unsigned long flags;
-	struct sk_buff *result;
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-	save_flags(flags);
-	cli();
-
-	IS_SKB_HEAD(list);
-
-	result = list->next;
-	if (result == list) {
-		restore_flags(flags);
-		return NULL;
-	}
-
-	result->next->prev = list;
-	list->next = result->next;
-
-	result->next = NULL;
-	result->prev = NULL;
-	list_->qlen--;
-	result->list = NULL;
-	
-	restore_flags(flags);
-
-	IS_SKB(result);
-	return result;
-}
-
-struct sk_buff *__skb_dequeue(struct sk_buff_head *list_)
-{
-	struct sk_buff *result;
-	struct sk_buff *list = (struct sk_buff *)list_;
-
-	IS_SKB_HEAD(list);
-
-	result = list->next;
-	if (result == list) {
-		return NULL;
-	}
-
-	result->next->prev = list;
-	list->next = result->next;
-
-	result->next = NULL;
-	result->prev = NULL;
-	list_->qlen--;
-	result->list = NULL;
-	
-	IS_SKB(result);
-	return result;
-}
-
-/*
- *	Insert a packet before another one in a list.
- */
-void skb_insert(struct sk_buff *old, struct sk_buff *newsk)
-{
-	unsigned long flags;
-
-	IS_SKB(old);
-	IS_SKB(newsk);
-
-	if(!old->next || !old->prev)
-		printk("insert before unlisted item!\n");
-	if(newsk->next || newsk->prev)
-		printk("inserted item is already on a list.\n");
-
-	save_flags(flags);
-	cli();
-	newsk->next = old;
-	newsk->prev = old->prev;
-	old->prev = newsk;
-	newsk->prev->next = newsk;
-	newsk->list = old->list;
-	newsk->list->qlen++;
-
-	restore_flags(flags);
-}
-
-/*
- *	Insert a packet before another one in a list.
- */
-
-void __skb_insert(struct sk_buff *newsk,
-	struct sk_buff * prev, struct sk_buff *next,
-	struct sk_buff_head * list)
-{
-	IS_SKB(prev);
-	IS_SKB(newsk);
-	IS_SKB(next);
-
-	if(!prev->next || !prev->prev)
-		printk("insert after unlisted item!\n");
-	if(!next->next || !next->prev)
-		printk("insert before unlisted item!\n");
-	if(newsk->next || newsk->prev)
-		printk("inserted item is already on a list.\n");
-
-	newsk->next = next;
-	newsk->prev = prev;
-	next->prev = newsk;
-	prev->next = newsk;
-	newsk->list = list;
-	list->qlen++;
-
-}
-
-/*
- *	Place a packet after a given packet in a list.
- */
-void skb_append(struct sk_buff *old, struct sk_buff *newsk)
-{
-	unsigned long flags;
-
-	IS_SKB(old);
-	IS_SKB(newsk);
-
-	if(!old->next || !old->prev)
-		printk("append before unlisted item!\n");
-	if(newsk->next || newsk->prev)
-		printk("append item is already on a list.\n");
-
-	save_flags(flags);
-	cli();
-
-	newsk->prev = old;
-	newsk->next = old->next;
-	newsk->next->prev = newsk;
-	old->next = newsk;
-	newsk->list = old->list;
-	newsk->list->qlen++;
-
-	restore_flags(flags);
-}
-
-/*
- *	Remove an sk_buff from its list. Works even without knowing the list it
- *	is sitting on, which can be handy at times. It also means that THE LIST
- *	MUST EXIST when you unlink. Thus a list must have its contents unlinked
- *	_FIRST_.
- */
-void skb_unlink(struct sk_buff *skb)
-{
-	unsigned long flags;
-
-	save_flags(flags);
-	cli();
-
-	IS_SKB(skb);
-
-	if(skb->list)
-	{
-		skb->list->qlen--;
-		skb->next->prev = skb->prev;
-		skb->prev->next = skb->next;
-		skb->next = NULL;
-		skb->prev = NULL;
-		skb->list = NULL;
-	}
-#ifdef PARANOID_BUGHUNT_MODE	/* This is legal but we sometimes want to watch it */
-	else
-		printk("skb_unlink: not a linked element\n");
-#endif
-	restore_flags(flags);
-}
-
-void __skb_unlink(struct sk_buff *skb)
-{
-	IS_SKB(skb);
-
-	if(skb->list)
-	{
-		skb->list->qlen--;
-		skb->next->prev = skb->prev;
-		skb->prev->next = skb->next;
-		skb->next = NULL;
-		skb->prev = NULL;
-		skb->list = NULL;
-	}
-#ifdef PARANOID_BUGHUNT_MODE	/* This is legal but we sometimes want to watch it */
-	else
-		printk("skb_unlink: not a linked element\n");
-#endif
-}
-
-/*
- *	Add data to an sk_buff
- */
- 
-unsigned char *skb_put(struct sk_buff *skb, unsigned int len)
-{
-	unsigned char *tmp=skb->tail;
-	IS_SKB(skb);
-	skb->tail+=len;
-	skb->len+=len;
-	IS_SKB(skb);
-	if(skb->tail>skb->end)
-		panic("skput:over: %p:%d", __builtin_return_address(0),len);
-	return tmp;
-}
-
-unsigned char *skb_push(struct sk_buff *skb, unsigned int len)
-{
-	IS_SKB(skb);
-	skb->data-=len;
-	skb->len+=len;
-	IS_SKB(skb);
-	if(skb->data<skb->head)
-		panic("skpush:under: %p:%d", __builtin_return_address(0),len);
-	return skb->data;
-}
-
-unsigned char * skb_pull(struct sk_buff *skb, unsigned int len)
-{
-	IS_SKB(skb);
-	if(len>skb->len)
-		return 0;
-	skb->data+=len;
-	skb->len-=len;
-	return skb->data;
-}
-
-int skb_headroom(struct sk_buff *skb)
-{
-	IS_SKB(skb);
-	return skb->data-skb->head;
-}
-
-int skb_tailroom(struct sk_buff *skb)
-{
-	IS_SKB(skb);
-	return skb->end-skb->tail;
-}
-
-void skb_reserve(struct sk_buff *skb, unsigned int len)
-{
-	IS_SKB(skb);
-	skb->data+=len;
-	skb->tail+=len;
-	if(skb->tail>skb->end)
-		panic("sk_res: over");
-	if(skb->data<skb->head)
-		panic("sk_res: under");
-	IS_SKB(skb);
-}
-
-void skb_trim(struct sk_buff *skb, unsigned int len)
-{
-	IS_SKB(skb);
-	if(skb->len>len)
-	{
-		skb->len=len;
-		skb->tail=skb->data+len;
-	}
-}
-
-
-
-#endif
-
-/**************************************************************************
-
-      Stuff below this point isn't debugging duplicates of the inlines
-      used for buffer handling
-      
-***************************************************************************/
-
 /*
  *	Free an sk_buff. Release anything attached to the buffer.
  */
 
 void __kfree_skb(struct sk_buff *skb)
 {
-#if CONFIG_SKB_CHECK
-	if (skb == NULL)
-	{
-		printk(KERN_CRIT "kfree_skb: skb = NULL (from %p)\n",
- 			__builtin_return_address(0));
-		return;
-  	}
-	IS_SKB(skb);
-#endif
 	if (skb->list)
-	 	printk(KERN_WARNING "Warning: kfree_skb passed an skb still on a list (from %p).\n",
-			__builtin_return_address(0));
+	 	printk(KERN_WARNING "Warning: kfree_skb passed an skb still "
+		       "on a list (from %p).\n", __builtin_return_address(0));
 
 	dst_release(skb->dst);
-
 	if(skb->destructor)
 		skb->destructor(skb);
 	kfree_skbmem(skb);
@@ -607,15 +115,14 @@
 struct sk_buff *alloc_skb(unsigned int size,int priority)
 {
 	struct sk_buff *skb;
-	int len;
 	unsigned char *bptr;
+	int len;
 
-	if (in_interrupt() && priority!=GFP_ATOMIC) 
-	{
+	if (in_interrupt() && priority!=GFP_ATOMIC) {
 		static int count = 0;
 		if (++count < 5) {
-			printk(KERN_ERR "alloc_skb called nonatomically from interrupt %p\n",
-				__builtin_return_address(0));
+			printk(KERN_ERR "alloc_skb called nonatomically "
+			       "from interrupt %p\n", __builtin_return_address(0));
 			priority = GFP_ATOMIC;
 		}
 	}
@@ -625,25 +132,23 @@
 	 *	'alignment mask'.
 	 */
 	 
-	size=(size+15)&~15;		/* Allow for alignments. Make a multiple of 16 bytes */
+	/* Allow for alignments. Make a multiple of 16 bytes */
+	size = (size + 15) & ~15;
 	len = size;
 	
-	size+=sizeof(struct sk_buff);	/* And stick the control itself on the end */
+	/* And stick the control itself on the end */
+	size += sizeof(struct sk_buff);
 	
 	/*
 	 *	Allocate some space
 	 */
 	 
-	bptr=(unsigned char *)kmalloc(size,priority);
-	if (bptr == NULL)
-	{
+	bptr = kmalloc(size,priority);
+	if (bptr == NULL) {
 		atomic_inc(&net_fails);
 		return NULL;
 	}
-#ifdef PARANOID_BUGHUNT_MODE
-	if(skb->magic_debug_cookie == SK_GOOD_SKB)
-		printk("Kernel kmalloc handed us an existing skb (%p)\n",skb);
-#endif
+
 	/*
 	 *	Now we play a little game with the caches. Linux kmalloc is
 	 *	a bit cache dumb, in fact its just about maximally non 
@@ -653,7 +158,7 @@
 	 */
 	atomic_inc(&net_allocs);
 	
-	skb=(struct sk_buff *)(bptr+size)-1;
+	skb = (struct sk_buff *)(bptr + size) - 1;
 
 	atomic_set(&skb->count, 1);		/* only one reference to this */
 	skb->data_skb = skb;			/* and we're our own data skb */
@@ -672,16 +177,14 @@
 	memset(skb->cb, 0, sizeof(skb->cb));
 	skb->priority = SOPRI_NORMAL;
 	atomic_inc(&net_skbcount);
-#if CONFIG_SKB_CHECK
-	skb->magic_debug_cookie = SK_GOOD_SKB;
-#endif
 	atomic_set(&skb->users, 1);
-	/* Load the data pointers */
-	skb->head=bptr;
-	skb->data=bptr;
-	skb->tail=bptr;
-	skb->end=bptr+len;
-	skb->len=0;
+
+	/* Load the data pointers. */
+	skb->head = bptr;
+	skb->data = bptr;
+	skb->tail = bptr;
+	skb->end = bptr + len;
+	skb->len = 0;
 	skb->inclone = 0;
 	return skb;
 }
@@ -705,10 +208,7 @@
 
 	/* don't do anything if somebody still uses us */
 	if (atomic_dec_and_test(&skb->count)) {
-
-		int free_head;
-
-		free_head = (skb->inclone != SKB_CLONE_INLINE);
+		int free_head = (skb->inclone != SKB_CLONE_INLINE);
 
 		/* free the skb that contains the actual data if we've clone()'d */
 		if (skb->data_skb != skb) {
@@ -730,16 +230,12 @@
 	struct sk_buff *n;
 	int inbuff = 0;
 	
-	IS_SKB(skb);
-	if (!skb->inclone && skb_tailroom(skb) >= sizeof(struct sk_buff))
-	{
+	if (!skb->inclone && skb_tailroom(skb) >= sizeof(struct sk_buff)) {
 		n = ((struct sk_buff *) skb->end) - 1;
 		skb->end -= sizeof(struct sk_buff);
 		skb->inclone = SKB_CLONE_ORIG;
 		inbuff = SKB_CLONE_INLINE;
-	}
-	else
-	{
+	} else {
 		n = kmalloc(sizeof(*n), priority);
 		if (!n)
 			return NULL;
@@ -775,8 +271,6 @@
 	 *	Allocate the copy buffer
 	 */
 	 
-	IS_SKB(skb);
-	
 	n=alloc_skb(skb->end - skb->head, priority);
 	if(n==NULL)
 		return NULL;
@@ -806,7 +300,6 @@
 	n->seq=skb->seq;
 	n->end_seq=skb->end_seq;
 	n->ack_seq=skb->ack_seq;
-	n->acked=skb->acked;
 	memcpy(n->cb, skb->cb, sizeof(skb->cb));
 	n->used=skb->used;
 	n->arp=skb->arp;
@@ -816,7 +309,6 @@
 	n->stamp=skb->stamp;
 	n->destructor = NULL;
 	n->security=skb->security;
-	IS_SKB(n);
 	return n;
 }
 
@@ -830,8 +322,6 @@
 	 *	Allocate the copy buffer
 	 */
  	 
-	IS_SKB(skb);
-	
 	n=alloc_skb(skb->truesize+newheadroom-headroom-sizeof(struct sk_buff), GFP_ATOMIC);
 	if(n==NULL)
 		return NULL;
@@ -862,7 +352,6 @@
 	n->seq=skb->seq;
  	n->end_seq=skb->end_seq;
 	n->ack_seq=skb->ack_seq;
-	n->acked=skb->acked;
 	n->used=skb->used;
 	n->arp=skb->arp;
 	n->tries=0;
@@ -872,7 +361,6 @@
 	n->destructor = NULL;
 	n->security=skb->security;
 
-	IS_SKB(n);
 	return n;
 }